Have you studied how things work in cryptography? Or just in Bitcoin? You've registered recently and you keep trying to find a way to cheat the system. Cheating the system isn't as easy as it seems. It's way harder than you thing and infeasible if each user was cautious enough.
I found that each and every single bitcoin in the universe is in danger cuz i found a critical security flaw in bitcoin protocol that would give me infinity private keys and all that private keys work.
This isn't a nice wording. First off, you'll have to define us what you mean by saying “infinity”. Infinite different keys? If yes, then that's impossible, because there's a specific number of available private keys.
Specifically, you cannot pick a number outside the following range as a private key:
[1, 115792089237316195423570985008687907852837564279074904382605163141518161494336]
1. Who maintains and develop bitcoin and its technology?
You're probably referring to the developers. They don't maintain Bitcoin; this task is being managed collectively by the network. They're the ones who contribute by coding.
Here they are:
https://github.com/bitcoin/bitcoin/graphs/contributors2. Can the developer modify the bitcoin protocol?
Anyone can.
3. To whom can I report this security flaw? (I'm always white hat)
To whoever you report it, if it's indeed a security flaw, we'll all gonna learn it.