I selected partially the torso and arms and made a duplicate out of the selection, with the idea of creating a coat to cover the body. The thing is that i did a temporal join of the arms and torso, explaining the face clipping here:
What i want from this is a way to clip those leftovers inside the arm's circumference, and those little faces clipping over inside the torso, without deleting the entire face because it'll leave a gap and therefore the solution will be doing it manually.
I'm not familiarized with some of the tools that blender brings to the table, so I dont know if what I'm requesting is possible without doing it manually.
EDIT: So i tried the first suggestion of using the Boolean modifier, and after messing around with the settings, i got what i wanted but there were tiny faces still clipping through, so it might not work for me because it requires exact precision from me.
Then tried the second suggestion of using Intersect (Boolean) from the face panel in Edit mode, and it works! Got confused by a second because i thought it'll automatically get rid of the leftovers, but just cuts them so you just select and remove, and thats what i needed.
Just adjust some parts of the geometry and im good to go!