Hola,
I’m a native Spanish speaker from Spain (I live in the U.S., spoke English all my life with a native English speaking father and my English could be better than my Spanish). Since I am Spanish, we use vosotros. While I heard people in the U.S. learn “ustedes comen”, I would say “vosotros coméis”.
My Spanish is mostly Rioplatense-based so I typically use “ustedes”. I do try to memorise the verb conjugations for “vosotros” though, mostly for reading/listening.
Then for the singular I typically use “vos” most of the time, and “usted” in the formal. I don’t know exactly the rules; frankly I simply hack it through Portuguese, if I feel like I’d call the person “o/a senhor[a]” I use “usted”, otherwise I use “vos”. But just like the above I try to memorise the “tú” conjugations.