on sha256 security bit are only 128, and quantum computer can break this(i can't find the article), if today pc can break 64 quantum computer can break at least the double of that
so bitcoin will need an hard fork in the future to survive
Stop talking nonsense. Quantum computers can't break SHA256 (used for hashing) without brute forcing it unless a flaw in it has been found. There is no article to link. I'm not saying that someone won't find a way to attack it in the future though.
you are wrong it can break 128 key(the power of quantum computer is like a pc that halve the difficulty, and if today pc, tons of them, could break 64, then a quantum can break 128) this is not enough to break sha256(or the private key which is 256 bit) i know, i didn't explain it well, but it is enough to break the pubblic key which is 128 bit