How can I get my daughters passport if her father won’t sign for it?

You both must apply unless you can prove sole custody which does not appear to be the case.

What exactly are the requirements for getting papers for your parents? Do you have to live with them until you're 21?

Assuming the mother is otherwise eligible for a green card, and your facts do not provide enough information about this, then just file an AR-11...

a copy of the divorce decree for immigration

Order the divorce certificate online to bring to the interview. Originals can be requested.

Regarding H1B maximum stay who used to work on L1B?

Working without a valid visa is illegal and subjects you to removal. Seek experienced immigration legal assistance.

There is no restriction as long as the B visa is valid and he leaves the US before its expiration and any different expiration date on his I-94...

Follow your employer's attorney's advice and carry copies.

Can I join another employer when my current H1B transfer is in progress?

1. Yes if premium processing is used (Form I-907 plus $1,410 filing fee). The employer applies for this. 2. Yes, this is possible.

Got an RFE for I539 Stating that Intentionally and Severely Injuring any Person wasnot filled? Actually the answer was "NO".

You must timely answer both questions completely and truthfully or the REF could become a denial. Good luck.

Can I apply for green card while in USA(brother is citizen), I lost my job while on holiday and found job?

Your prospective employer needs to apply for a work visa for you. if successful, you must leave the US (before your I-94 authorized stay expires),...

In I-539A form under Provide Information about your most recent entry into US section, which passport number should I enter?

Answered already. Use old number on the form and enclose a copy of your new passport and advise re same in cover letter.