

First step is to shrink and possibly move around your existing partitions to make space for a new one. GParted Live may help with that. Once you have enough space, just install Arch there. If you already have separate /home you should be able to reuse it.
You’re so gracious that you allow people to pay to be beta testers for your proprietary app.
(Also, I hate to be that guy who calls everything AI generated based on some tiny markers, but the use of emojis makes me feel the post is AI generated with no, or minimal, human oversight which puts in question quality of your code).