A person on F1 visa frequent and active selling online requires USCIS authorization.

Yes, if arrested then there's probably immigration issue. You are encouraged to consult with an immigration attorney for further review and guidance.

Your parents can apply to come here on a US visitor's visa. Thier plan to live in Canada helps overcome the potential "immigrant intent" problem.

A timely and correctly filed I539, allows your stay and employment within the validity of H1 and I94.

It is up to you. Either file the medical with initial application or take it with you to interview.

If denied visa here and/or abroad or abroad, answer "yes."

Send a writing request to withdraw your I90 because you found a missing PRC.

Filing I1165 concurrently with I485 gives you a work permit AED.

Check with your local DMV schedule to determine when you get your DL. USCIS does not control or administer the issue of DLs.

It appears your case is moving along just fine. Congrats!