When do you use で and when do you use へ?

Question:

Im a little confused...

i.e. departo で \ へ ikimasu.

Answer:

で is the location where something takes place. It also expresses a means of doing something
EX:
レストランでてんぷらを食べました (resutoran de tenpura wo tabemashita)
I ate tempura AT a restaurant.
辞書で言葉を調べました (jisho de kotoba wo shirabemashita)
I looked up a work USING a dictionary

へ is the destination that one is moving towards
EX:
飛行機で東京へ行きました (hikouki de toukyou he ikimashita)
I went TO Tokyo BY plane.