Surprised no one's suggested Stardew Valley yet.

Games similar to portal:

• The Talos Principle 1 & 2
• Antichamber
• Superliminal
• Viewfinder
• Manifold Garden

Similar to Firewatch:

• Umurangi Generation
• Return of the Obra Dinn

Other stuff that might interest you that I haven't seen already recommended:

• Journey
• Abzu
• Exo One
• Wytchwood
• Cairn (tentatively. This game can get stressful)
• Dinkum
• Untitled Goose Game
• A Lego game (Any of them. They all follow the same formula)
• Flower

No idea if any of those work on Mac though. If you have an intel based mac you can use bootcamp to dual boot windows, and unlock maaaaany games.

No Mans Sky is my chill game.

You are looking for cozy games or walling simulators.
Honestly I don't know what's on macos, but a quick search: stardew valley, my time on portia (i recommend sandrock if it's available), slime rancher. For exploration: The Stanley Parable, Life is Strange.

• Blue Prince
• Chants of Senarr
• Outer Wilds
• Secrets of Blake Manor

Monument Valley?

I enjoyed Portal because I had to plan out what I’m doing before I act (without being pressured to act), the atmosphere of the game was legendary and I liked that little robot following me

Portal 2 has two community made "Valve Quality" DLCs. "Portal Stories: Mel" and "Portal: Revolution". Mel seems playable on macOS at least. Revolution is basically a Portal 2 presequel. (It's also so long I would have payed for it.)

Suuuuper confused no one mentioned The Witness yet. Probably the best calm game of our time.

Talos Principal 1 and 2. They are also story based puzzle games. I'm not sure I'd Talos 1 remaster or 2 are on Mac but I'm sure the original one is, which still holds up.

A Short Hike

The Outer Wilds

Tunic

Exploration focused games that are pretty calm (for the most part). They are some of my personal favorites. I recommend not looking up much about them (especially Outer Wilds and Tunic. Learning mechanics from gameplay is part of the game for those two). Tunic is probably the most action oriented of the lot, (like old Zelda games) and it leans hard on the puzzle aspect, so if that's not your favorite then it might not be for you.

A Short Hike! Play as a little bird, climbing a mountain, flying/gliding, talking to quirky characters. Beautiful pixel art. Also Fez.

In addition to these, I would add Superliminal. Do not confuse it with Subliminal, that one is not chill 🤣

Viewfinder is good if you want a game where you need to figure out how to get through each level.

Eastshade is the chilliest game I know. Also great music.

Anything Myst too.

Dorfromantik is also relaxing.

I would recommend Stray but it has some areas where you're running away from bad things for a bit.

Mostly it's just exploring and meowing though.

Maybe try GRIS. It's a 2D platformer journey with amazing presentation.

What Remains of Edith Finch. If you liked Firewatch, you will like this one too. It's short, roughly 2 hours to complete, and I recommend you do it in a single sitting. And provide some tissues.

If you like eerie (but not scary) vibes, I also recommend Kentucky Route Zero

I enjoy calmer games most times I'm gaming so I have a lot. The genre I most like is puzzle games, but there are a few exploration/ walking simulators here, too. Among the games already listed, there are:

• The Room
• Doors
• Boxes
• Machinka Museum
• My Brother Rabbit
• The Gardens Between
• Stela
• La Rana
• Dawn
• Manifold Garden
• Discolored
• Tree Bonzai

You could check out "FAR: Lone Sails". It's a pretty chill game where you have a machine that you're sailing/driving through platforming actions to the right. It has cinematic feel and a kind of environmental plot, but I don't think there's any way to lose or anything...

And if you like it, there's a sequel "FAR: Changing Tides" that is very similar, but longer and with a more complicated machine to manage.

I could see people being bored with it, there are "puzzles" but they're super light, but maintaining the machine scratches something within me.

The Entropy Centre is a largely Portal-inspired game that will require you to plan out what you're doing even more than Portal. (Note: there are a few chase sequences and a few battle ones that break this pattern.) And there's a cute robot called E, and your portal-gun-equivalent has an AI too. Basically, it's Portal but the AIs are friendly.

And then there's The Talos Principle series, which is even more like what you're looking for.

Escape Game Simulator - puzzles, no pressure, exploring encouraged.

Crime Scene Cleaner - no stress, but a little spooky, very relaxing

Slime Ramcher - turn off tarrs and explore. Breadcrumb story, great music and sound effects.

Gone Home is a lovely game, the story is a bit sad, and parts has a creepy vibe, but it is interesting and well worth a playthrough, it is more similar to Firewatch than Portal.

Minecraft on easy mode can be a good calm game with friends, let's you build and explore together without much pressure.

I really love Flower

https://youtu.be/0IS9sGGuvYo?t=0

Terra Nil. It's about rehabilitating a devastated ecosystem..

Also I'd just like to say that I hate Wheatley. He's such a slimy, manipulative little dullard. He let nearly everyone in the Relaxation Vault die through incompetence, decided to run away from his failures, woke up GLaDOS, accused a mute woman of bossing him around, and nearly got everyone killed for a second time.

Also also, there's more Portal you haven't played yet. There are fanmade spinoffs that run as mods to the original game, with new stories, characters, lore, voice acting, and puzzles.

Portal Stories: Mel is a 6/10 spinoff about an Olympic athlete named Mel, who awakens from hibernation some time before Portal 2. It's in between the lengths of the original two games. It has a couple new interactions between existing mechanics, but the puzzles are kinda easy. Prepare yourself for a bad Cave Johnson impression.

Portal Revolution is an 8/10 spinoff about as long as Portal 2, which takes place after Portal 1 as Aperture is beginning to fall apart. The puzzles are a nice medium difficulty with one or two great head scratchers. It introduces a few new testing apparati, and there's an extended sequence with the single portal device where you need to think creatively. The characters are well written and well acted, and the boss fight is very cool.

Portal Reloaded is a 7/10 spinoff where you can shoot a third portal that lets you travel through time. It's very hard, and the story is almost nonexistent (at least as far as I've gotten). Play this one if you think the others are too easy.

The Aperture Science Paint Gun Initiative is, uh, bad, I've heard. This one replaces your portal gun with a gel sprayer. I haven't played it yet, I might skip it.

The Talos Principle is amazing and the sequel is super good too. Devs recently came out with a remaster of the first game too.

Outer Wilds is a masterpiece, although it's not completely chill at all times (actually can be scary but only rarely and you can disable that too). But it's a really really really good game.

I can highly recommend Tinykin, no enemies, nice locomotion and controls

The first Kerbal Space program?

Timberborn?

Disco Elysium?

If you don't mind turnbased then a whole bunch of stuff.

Hardspace: Shipbreaker in sandbox/unlimited mode

Factorio on peaceful settings is pretty calm

I really like Kingdom Two Crowns, especially the Nordic biome. It's pixel graphics so not for everyone, but so beautiful. The gameplay is repetitive but satisfying. There are enemies, but they're not that hard. It's beautiful

Space Sprouts: calm, cosy, whimsical, physics based.

Opus Magnum: machine-building puzzles loosely based on alchemical lore. The puzzle objectives tie into a story that is kind of just window dressing, but interesting enough.

I really enjoyed playing the Myst and Riven remakes. Definitely give them a shot. Especially Riven.

Untitled Goose Game

Blue Prince

Rime!! No one ever suggests it but it's such an amazing game. You can finish the story in 5-10 hours probably, but you'll be thinking about it far longer than that

Portal Stories: Mel

I recommend Timberborn. Also great and relaxing to watch someone like Zeddic play it.

Subnautica

Unravel and Unravel Two are very cosy platformers.

Transistor and Bastion are similar games that can be chill with combat.

Thomas was alone is a chill platformer with a nice story.

no man's sky, always relaxes me after a tough day