What will happen if I lose all my reputation by asking bullshit question?
Your reputation will go to 1, and you won't be able to do anything except post, suggest edits, and accept answers. If you ask too many low quality questions after being asked not to, there's a chance you will get suspended, too.
Please don't deliberately ask bad questions.
It's actually pretty hard to lose all of your reputation. There is a major imbalance between reputation gains and losses. For example, if a question gets upvoted you get 5 reputation but if it gets downvoted you only lose 2. See How does "Reputation" work?
You'd have to put in a lot more effort to lose reputation than you have to put in to gain it. You'd get suspended way before that happened.