This is very important advice if you want to have a good time playing the game. Picking the right lobby is changes your experience drastically.
and also at least in lobbies with noob in the name its pretty rare for people to be actively hostile to the low os ppl who at least know the basics. but you do have to remember that in the middle of a match nobody has time to type and tell you what to do politely.(its an apm heavy game). try to assume good intent, its not ppl being rude usually.