For 1. Duration of time:....................... We walked for two hours. 2. Distance:.................................. I ran for five kilometers. 3. Purpose:................................... I bought this jacket for you / Let's meet for lunch 4. In the direction of:...................... She left for New York. 5. In favor of/supporting an idea:..... We are for the proposal / I am for free speech. 6. Considering:.............................. The boy is clever for his age. To 1. In the direction of:.................... Turn to the right / Drive to the north. 2. Destination:............................. I am going to Rome. 3. Until:....................................... from Monday to Friday / five minutes to ten 4. Compared with:....................... They prefer cricket to soccer 5. With indirect object:................. Please give it to me / give something to someone. 6. As part of infinitive:.................. I like to ski / he wants to help. 7. In order to:.............................. We went to the store to buy soap.

That's a difficult question to answer completely. 'To' and 'For' both have many different purposes in English. Unfortunately, often it's easier/better just to learn these as part of verb phrases than to try to think of them as single words. If you're just comparing these as prepositions, the easiest way to think about it may be this: 'to': direct action / direction "I give something TO you" [A -> B, no interruptions on the way] 'for': * indicates purpose or cause [ it almost answers the question 'why' ] * on the behalf of. "I got something FOR you"

This is too complicated and general to answer here simply. This video might help: https://m.youtube.com/watch?v=9MaksI4cNQE