What is a notice in petition to an attorney general?

More info is needed in order to provide a substantive response.

Assuming you have no employment contract, your employer can fire you for any reason or no reason.

You are correct that you must be paid at least the equivalent of minimum wage for all hours worked, including meetings.

Is it wrongful termination if my employer falsely accused me and called me a liar in front of other employees?

You have not stated any facts that indicate a basis for a lawsuit.

Can I sue my employer?

Your only remedy for this injury is to file a workers comp claim.

A business-man owes me 8,000.00dlls and he is threatening me

Sue him in small claims court. You will have to prove he actually owes the money. Did he sign a note? Did he send you email acknowledging the loan?

My previous employer laid me off and awarded me with several weeks of severance. I found a new job thereafter. Before joining

If you did not have an employment contract this termination was not wrongful.

Nice try, but no. The state would not be bound by such a contract.

Can my employer force me to stay on the premises for 10-12 hours a day?

If you are really exempt, and not merely misclassified as such, your employer can do this. If you don't like if (and I don't blame you if you...

What if your damage estimate is just $800, then after repair it went up to $1100? Do I have to report it to DMV?

You are required by law to report this accident.