1. Most of your games should just work fine these days. If you're playing live service shooters (usually competitive ones, think Valorant and such) you may have issues with their anti-cheat not liking Wine/Proton, but everything else is usually fine. You can check if your games work here https://www.protondb.com/ and here https://areweanticheatyet.com/
2. Pretty much every emulator has a Linux native build, or can be built yourself for Linux with minimal effort. I've never had issues with things like Dolphin, Xemu, pcsx2, etc.
3. OBS Studio runs natively on Linux and works great.
4. Godot also runs natively on Linux and works great. If you're using other tools in your workflow like Adobe products, you may have issues, but there are a ton of free and open-source alternatives.

And honestly, for distribution, I'd just use Ubuntu. I know I'm probably going to get a lot of flack for saying that, but Ubuntu is much better than Linux Mint and Co. simply because it is more up-to-date (nerd speak, can ignore: Wayland being the biggest thing, Cinnamon is still pretty far behind in this department, and slapping KDE Plasma or GNOME onto Linux Mint has been known to cause issues) than other distributions. It also has the benefit of having the ability to install proprietary codecs and drivers (think Nvidia graphics drivers) out of the box unlike other distributions people like to recommend such as Fedora. Just know whatever distribution you use, at the end of the day, 98% of the software is the exact same across each distribution and there will be no noticeable difference between them for a new user really. If you can get comfortable with 1 Linux distribution, you will be able to get comfortable with any distribution fairly quickly with minor changes.