I know this is a pretty common question, but the Google results don't seem to offer a good solution and are mostly aimed at people who already know Linux.

I am looking to switch from Windows, where I have my OS and whatever big game I'm currently playing on my 128GB SSD, and everything else (games, most software, documents, ect.) on my 2TB HDD. ELI5, How would I replicate this on Linux? I'm planning on installing Mint, but am open to using Bazzite if it offers any additional tools for this sort of this.