How many days my mother has to do after his first visit to USA before to come back with his visa b2 for a second time?

I agree with my colleague. Generally your mother should wait 6 months after she leaves the US to come back. Otherwise it may look like she is...

Please do I have to pay for renewal filling fee for my I-765 EAD, while my I485 form is still pending?

I agree with my colleague. Generally the receipt notice for your renewal will extend your work authorization for another year.

What can I do?

Generally you would want to apply for the renewal of your EAD as the receipt notice usually extends your work authorization for a year. Since you...

Will the i 751 receipt notice become invalid once your 10 year green card is approved?

She will be allowed to reenter the US with the I-751.

Unfortunately, CBP has broad discretion for tourist visas. Generally a tourist visa is only supposed to be for 6 months in a calendar year. If you...

Can change my address ?

You need to file an AR-11 with your new address. Since you are applying for asylum, you definitely should have an attorney assist you.

Currently not working but made over the poverty line this year, can i sponsor my spouse for affidavit of support?

You should definitely try to find a joint sponsor. USCIS has places a lot more scrutiny on the I-864. So it would be better to have a joint -sponsor.

Can I petition for my dad to come to the U.S. after he got married to my step-mom?

Yes you can petition for your dad regardless of his marital status when you turn 21.

I407 advised on my passport

You should meet with an attorney before you any international travel. One month is not sufficient time to be granted advance parole. It appears...

Can you revoke form I-864 joint sponsor after the case is complete?

Generally the answer is no. You should have read the form carefully before you signed it. You are financially responsible until the green card...