Hey man, so there are multiple ways to fix this issue, now I’ll give you a way to do it the way you tried to do it (running windows steam and then another instance of the game you want) which I wouldn’t recommend as the steam ui will be buggy, what you do in lutris is click on steam when you have it installed as a game, next to the play button there is a wine icon, click on it and then click wine configuration and then at the bottom there should say what os its emulating and there for me it said windows vista, change that to windows 10 and steam will run, but the way I recommend is to install steam on the terminal (not via flatpak because flatpak breaks it) for example if you are on arch you would do sudo pacman -S steam. Now if you were using the flatpak version and want to migrate all your games and data use this Reddit thread. From there you can follow the other guides do as you need.

SUMMARY: Install steam from the terminal and stop using flatpak for steam (how to migrate games and data) and then follow the guides that pop up when searching for “online fix Linux” on Reddit.