Confusing English can someone help?

1) had had is the pluperfect tense the first had is the helping verb, and the second is the past participle. (kinda confusing when it looks like the same word).
I had is the simple past tense.
to use a different verb: I had given two apples to my sister...I gave two apples to my sister...there is a difference in the timing.

2. they are all the same...the first two simply stress that you had finished before whatever comes next in the conversation.

3) neither makes sense, but: two wrongs don't make a right! (which means, if your friend hits you, and you hit him back, you haven't really fixed anything...he may have started it, but you were both wrong in the first place...something you say to two nine year old boys who are fighting...at least that's who I say it to most of the time)

1) Yes. It's as if you are telling a story about the past.

2) Numbers 1 and 3 are fine, and so is number 2 (except it's not that common to hear it said like that).

3) Sorry, but neither of these make sense.

1. the first one is incorrect, it'd have to be "i have had..." then it would mean that you did have them, but not anymore.
2. All of these are correct, although the 2nd one should only be used when it's being used as an answer.
3. I don't know about the first statement, it would sound better as "you can never" or as the full " you will never"
The second statement is fine, i've actually heard that one, it's similar to the you don't need to win to be triumphant idea.

1 i had 2 apples yesterday is proper grammar, I had had, is double positive which is not proper.

2 I've finished my work is correct. Yes the first two are wrong to say.

3 No, both of those are stupid becaus ehe is contradicting themselves, they say it doesnt matter whos right and then they say who is right