Which form to be filled by non immigrant applying for re-entry

You have too many questions for this small panel. The form is I-131..

How to become legal again

You need to check and see if your case has been referred by USCIS to the EOIR. If not, do not file a new petition, instead ask the USICSI to...

My H1B is going to expire on July 19 2017. Now Do I have option to start processing my Green Card through current employer?

Your best bet is to sit face to face with an immigration attorney and figure out your option.

You may wait or file for adjustment soon after marriage. either way consul with an immigration lawyer.

How can I apply a green card?

The only solution for your is to file for vawa if you entered into this marriage in good faith and you were emotionally abused. we all do...

Can i apply for adjustment of status later, after few months? Or do i need to do it immediately after marriage?

How do you know if you are not subject to the 2 year home residency? If you are not required then apply for adjustment now, but if you are, first...

New H1B application while H4 extension is pending.

Your H1B attorney who is filing your petition should be able to answer this question.

What should I do to change my status from J-1 to F-1?

If you are not subject to a waiver then no you may remain in US and continue your education.

What are my chances of applying for F-1 to pursue a second Bachelor's Degree?

You may start studying and revert to F-1 but there will be no more OPT.

I have F1 and my family friend wana sponsor me for his business as employee so how can I change my status from F1 to H1b.

Generally USCIS don't like to see family employment petition. However, i suggest that your consult with immigration lawyer.