I am a green card holder , currently in the process of getting my citizenship, how can I sponsor my to be wife who has OPT visa?

You can petition for her as a spouse of a LPR before obtaining your citizenship and upgrade your petition thereafter.

What another immigration process should I do to bring my mother to USA just to visit me?

You can apply for her permanent residency as a USC, particularly if she was previously denied on a tourist visa. Consult with an experienced...

Can my friend sponsor me to visit US?

No an applicant for a tourist visa applies on his own and does not require sponsorship.

What i should choose in DS 160 form ( propose of tripe ) ?

You should indicate the purpose of your visit which appears to be to visit your grandparents. Consult with an attorney for guidance re: applying.

How can my brother from Sweden live in US?

Your mother can petition for him but the wait would be many years. On the alternative he can seek to enter through employment based immigration but...

I’m a permanent resident, should I apply for my daughter over 21 now? or should you wait to become a citizen in 3 years?

You can start the petition now and when you become a USC upgrade the petition accordingly.

Do I have to pay taxes to the US government if I move to a different country and become a citizen there?

You should consult with a tax attorney or accountant for guidance.

File the I90 right away but depending on the service center it is taking between 6-8 months, possibly longer.

HOW CAN I GET MY SISTER to COME TO USA?

You can apply for her as a USC sibling although timing would be about 12-14 years. She can possibly enter on a tourist visa or other work visa. To...

What is the mailing address for concurrent I-130 & I-485?

You can refer to USCIS webpage for the direct mailing address for you based on the location of filing and method.