には

には is に with は added. After the dictionary form of a verb it means "to", "in order to": the sentence goes on to say what that takes – what is needed, how long, how hard. After a noun it puts a に phrase up as the topic.

には or ために

After "in order to" には, the second half is a judgement: ひつよう必要, たいせつ大切, かかる, きごう〜なければならない, べんり便利. For a plain action you take for a purpose, use ために.

• × 留学するには、お金をためています → 留学するために、お金をためています

"For": the person who judges

After a person, には gives whose ability or standpoint a judgement is measured against: "for", "to". It often comes with すぎる, わからない or できない.

に as the topic

Any に phrase – a place, a person you give something to – can take は to become the topic or to contrast with something else.