Considering the complexity of this situation, it highly advisable that you retain an immigration attorney. Alternatively, the only way to...

What is the difference between my mom sponsoring me and my brother sponsoring me?

Probably the same process. Your best bet may be a spousal application. More details are needed. Discuss with an experienced immigration attorney.

What I leave USA before my i539 extension approval during pandemic?

No, as long as you leave before the period your I-539 covers or file a new one.

Service by Publication is the best option in this scenario.

I-539 question ?

Consult with an experienced immigration attorney.

Your parents have to continue to file extension applications in 6 month increments. Talk to an immigration lawyer.

Can I go to jail for being on probation & a cops pulled me over saying I had drug paraphernalia for cigarillos ?

Yes, your probation officer will be notified if you're pulled over.

No, investing in stock would not count as a violation of your status.

I agree with the other responses. The first step would be to find out why and how the lien was cancelled.

How much would it be for my speeding ticket ?

You can find out by calling the phone number on the back of the ticket. You should talk to the court about keeping this off your record.