1) If you only perform a factory reset, you will be banned if you access the nintendo servers. Create a clean NAND backup before you make any modification to your switch and restore it when you want to go online again.Couple of questions
Is it possible to mod the switch, and then later reset it back to factory settings (to access nintendo eshop/social/etc)?
After modding, will I be able to access to game updates? while not getting banned on my nintendo account.
I am totally lost at what I should be doing or what I am seeing, but how do I install homebrew or w/e it is called?
2) Install game updates as NSP and don't download them on your switch. You shouldn't even have a internet connection on your hacked console.
3 Start here: https://guide.sdsetup.com