Pretty much. But if you need to test it, you can buy another drive and install linux and your games there. If it doesn’t work, you can use the extra drive for something else.

In Steam on Linux, use settings to enable Experimental or Proton for Windows games.

Edit: This is computer science, you must report your findings!

Here are some tips once you have chosen:

You can change your desktop environment later.

If you do your install with seperate partitions for /home and others, leave 10% unallocated. Also make /bin about 15gb and /boot about 1.5gb. When you eventually run out of space, you can use KDE Partition manager to add the unallocated space to the partition you need, even if you set up encryption (gparted doesn’t play well with encryption). You can install Partition manager as a package, you don’t need to use KDE Plasma.

Using a drive mirror is a good idea. Maybe use it the second time you install.

If you want to use a cool filesys like zfs, just use btrfs for now (licensing issues). Ext4 will also work for desktop user needs.

If you go with Debian, you can add repos to your /etc/apt/sources.list file. But it is a one-way trip, so before adding sid, consider running your program in a vm. Non-free non-free-firmware and contrib are fine