면 돌아가다

if X, go back or round

-(으)면 sets the condition; 돌아가다 is the part to watch, because it means several different things here. It is 'go back' (한 번 시작하면 돌아가기가 힘들어요, 'once you start it's hard to go back'), 'take the long way round' (직진하면 돌아가 30분, 'go straight and it's a thirty-minute detour'), and 'turn, run' for machines and channels (날개만 끼면 돌아가는). In the honorific 돌아가시다 it means to pass away, which is what one line here uses.