Random_Coffee: That's why I haven't seen it yet. I've seen a few Captain America films, two or three of the Thanos saga, a few Avengers.. but far from everything. There's just so much Marvel now. I probably know enough now to get some good enjoyment out of GotG though.
The Guardians movies can be perfectly watched as standalone movies, without knowing much of the Marvel universe, they don't really reference other movies other than mentioning Thanos at some point (and you already know that fella).
The later movies (Thanos saga) reference the Guardians, but not the other way around.
In Avengers Endgame and Infinity War the Guardians join the ensemble and continue to be present in Thor Love and Thunder, but before that (and that's the two movies), they are completely separated from the rest, they are all about Quill and his "adopted" family.
At least watch the first one, it's more than worth it.