1. Ignore the folks with way too much time on their hands who tie their self-worth to their ability to install Arch or whatever. Just use Ubuntu*; it's fine.

2. Once you install it, just use it like the normal desktop OS that it is. There's no need to immediately go down a !unixporn rabbit-hole just because the customizability of the system facilitates it. If something you need doesn't work or otherwise bothers you, fix it, but otherwise leave the system alone and just let yourself get used to it with default stuff.

3. By the time you get done with step 2, you'll be able to know for yourself what you want to do next.

Unnumbered: Gradually come to understand that the terminal is your friend, not something to be intimidated by. You shouldn't need to use it (not with Ubuntu, anyway), but if you give it a chance you'll eventually find yourself wanting to use it because of the advantages it has, such as using the history to have a perfect record of what you did, executing a complicated sequence of commands perfectly by pasting them in instead of trying to manually follow instructions clicking around in a GUI, and creating pipelines and scripts to do complicated things (say, batch-renaming files) relatively easily.

In particular, try to understand the essential nature of UNIX: "Think of the UNIX system programs as... the building blocks with which you can create things. And the thing that distinguishes the UNIX system from any other system is the degree to which those building blocks can be glued together in a variety of different ways -- not just obvious ways but in many cases very unobvious ways -- to get different jobs done"

(* Yes, specifically Ubuntu, not a "similar" distro like Debian or Mint or Pop! OS (let alone a dissimilar one like Arch or CentOS or Slackware). You want the distro that things like Steam officially support, not one that they unofficially work on. Picking a different "flavor" of Ubuntu that uses a different UI, like Kubuntu or Xubuntu, is fine though.)