You need to track your calories and macros. EVERY. SINGLE. DAY.
You can go overboard sometimes, but you still need to track the calories.
Someone else has recommended https://tdeecalculator.net/ which is a great starter point to set targets.
Eat whatever you want, but follow your macros targets: I'd recommend a macros target high in proteins.
That's literally why Bazzite is a better choice for a beginner: because it's harder to really break it.
I'm sure CachyOS is great but not for someone coming straight from Windows, unless they're happy to reformat every other week.
That must be quite expensive. Do you have a social deal? How much are you paying per month?