걷다
= to walk

걸어가다
= to walk to some place

걸어갈 거예요?
= Are you going to walk?

진짜 거기까지 걸어갔어요?
= Did you really walk all the way up there?

걷는 거 좋아해요.
= I like walking.

제 남자친구는 저랑 걸어가면서 다른 여자를 쳐다봐요.
= My boyfriend looks at other girls while walking with me.