F2a Green card approved. But medicals expire before entry into USA. Do i have to take medicals & interview again? Whats process

You don't have any problems

Maybe there is no need to worry. You must have health insurance now and will have for the last 15 days of your status. Maybe your baby won't have...

I didnt pass the citizenship intreview because i didnt meet the time required for the citizenship , when i can apply again ??

Yes you do but not until after you have spent 30 months in US out of the last 60 months before filing.

Will i be able to adjust status?

You will be able to adjust status only when your wife becomes a US citizen. Obviously now she is not for if she were you would be forgiven for...

Is the fact that I entered the U.S. under a false last name going to keep me from gaining citizenship?

Are you skipping the green card describing your plans? How can you apply for citizenship not having been a permanent resident unless you were born...

Can i apply to college within the U.S.? If so how?

There are so thousands of illegals who have attended college. I am not sure, though, you know the meaning of the word "illegal". If you entered...

Can I use the intending immigrant’s income to meet the income requirement in the Affidavit of Support Form?

Husband - I-864, you - I-864A.

Will taking my husband's last name help in proving marriage in good faith? Is it better to change it now before i start process?

You'd better focus on more important issues. Besides, if you are going to change your last name anyway, what's the purpose in waiting?

Can I apply for naturalization while staying in the US for 4 years 6 months plus 1 year as a student?

You can file 4 years 9 months after you got your green card. Just in case file in 4 years 10 months.

Can my mom who is a U.S. citizen petition for a green card for her mom (my grandmother) while I financially sponsor my grandma?

Yes, you mom can petition for her mom. Insufficiency of income is one thing, filing income tax returns is another. If you support her 100% then...