Q1: what kind of visa i should choose if i want to live in Japan for a long term? Q2: if i granted a 3 months visa and requested for 3 months extend that makes 6 months. can i ask another extend when it expired? or what should i do to stay in Japan on a longer term?

Did you actually read anything here before asking that??
This topic has been talked about A LOT already.

Spend 10 minutes reading.

i spent a few minutes reading the forums. really sorry but i cant find the answer that im looking for. can anyone please tell me How to Live in Japan permanently like years? i also want to be a citizen in japan, but i absolutely NO experience on immigrating to other country. can anyone please help me?

It has already been discussed here - citizenship too.
And the old dude made videos about it.

If you are too lazy to look and listen, nobody is going to waste time repeating everything just for you.

Hello,
Dao Chizen, Perhaps try your local Embassy or travel agency these people are very professional,they deal with many topics of travel also visa each day,They will have up to date changes or best information on hand,even using email to these places can be advantageous,at the end of the day get more than one opinion,go to more than one source,This is freedom of choice,make educated informed decision,Perhaps you could become Sumo or baseball professional to be awarded Citizenship in this way, both of these very popular in Japan.