Far is most common in questions and negative sentences, and after too and so.
- How far did you walk?
- I don’t live far from here.
- You’ve gone too far.
- ‘Any problems?’’ Not so far’ (=not up to now.)
In affirmative sentences, we usually use a long way.
- We walked a long way. (We walked far is possible, but not usual.)
- She lives a long way from here.