Oh okay, that actually seems like on the lower to middle end of things, all things considered.
One of the best things you can do is to check out the system requirements for some of those things you hope to run which can help give you an idea of what you’ll need.
For example, if you view the game House Flippers 2 on Steam, you’ll see the screenshot below which kind of gives you an idea of what you want to aim for in terms of the right pieces you’ll want to buy for your computer:

You’ll ideally want to go for the recommended or above the recommended for the best possible performance of the game. The minimum specs are the absolute lowest that can run this game at its most basic level, which will often not be the best quality or run at the best specs, so you don’t want to follow those.
What are some of the 3D modeling programs you hope to use? That will likely be more intensive, depending on what it is, than the gaming will be.
A great resource for building and budgeting a PC build is pc part picker: https://pcpartpicker.com/
If you’re not familiar with it, it basically helps you find and build a PC and shows you about how much it all will cost you. It’s also a great resource for new beginners since it guides you through exactly what is needed so you don’t end up surprised and have to make multiple trips to the store/purchases online.