I'd recommend looking at the self hosted/selfhosting communities on Lemmy for ideas.

Right now there's some annoying incestuous stuff going on with the main email services out there and "non-trust" of self-hosted email servers.

When setting up an email server, you'll need to purchase a domain name (recurring fee), set up the software on a server you can keep running 24/7 (if it's ever offline, mail can't get to it and it'll be recorded as offline/not real). You'll need to work with your ISP to try and get a static IP for your server, so it's always at the same "place" online. Then place it up so it is accessible to the Internet at large (security concerns, makes it an obvious target for automated scripts that hackers run to hijack stuff). Then you need to register the domain name as pointing to the server.

Then you need to set up proper email security settings on it like SPF records and DKIM so that outside recipients can verify that email from your server is in fact from you. That's a super simplified overview of what is officially "the bare minimum". As long as that explanation is, it is a "napkin sketch" level overview.

Now we get into the slimy part regarding Google, Microsoft, Apple, Amazon, and all the other major email providers. Having the standard email security set up is not enough for them to actually accept receiving email from your server. None of them publish the true requirements openly, but they basically require your email server to have existed for a long period of time with no issues to build trust, and to have handled a certain amount of email already. Which is a circular issue considering they don't trust email from your server, so how can they verify it has handled email well and not been a spam box?

Now you get into the grey market of email server "priming" services, that intentionally use your server as a spam box to generate enough "valid" email traffic to attempt to trick the major players into trusting you.

And again, this is just surface level, casual understanding of the problems you'll face.

Start with something not exposed to the Internet at large first for setting up your own server. Then maybe look into opening access to it from outside your personal network through tools like tail scale. Then maybe look at doing something with less strings attached as far as online hosting goes, like hosting a server for Minecraft, or the open source clone of it, Luanti.

I work in systems administration and systems engineering. The only people I know in tech or otherwise that are hosting their own email servers are people who started doing ages ago before the major players got so persnickety, so they were already "trusted" with a history of being good little email servers before the major players started tightening down their requirements for trust more and more and more.

It's not impossible by any means, but it's a hell of a project for someone so early into learning tech stuff that they'd word your post they way you did.

No offense meant, we all had to start somewhere, and I totally get why you'd want to host your own email. I want to host my own too. I'd just caution you to aim a little lower first and work your way up.