Is it affect uscitizenship

ِYou are required to disclose any arrest on your application.

Unmarried child under 21 of resident permanent, am I eligible?

Perhaps a year ago you had not overstayed your visa. This is a complex situation. Hire an experienced immigration attorney.

You are required by law to notify USCIS any change of address within 10 days or less if you are not US citizen and over 14. Long distance should...

I am a LPR and my girlfriend has a US visa. Can she travel to USA on that visa if we marry in our home country?

It is possible but there is no guarantee. She even may be able to extend her tourist visa after entering, but again it cannot be said for sure.

Can I apply for citizenship after 3 years if I won't leave the country?

More information is required. You have to specify whether you obtain your GC through marriage. If yes, you can apply after 3 years. Otherwise, you...

F1 to H4 EAD concurrent filling

It won't hurt to contact them and follow up.

Please only professional attorneys answer

I have a question for you: what does "please only professional attorneys answer" mean?

I'm on H1-B visa .. if i get layoff from current job, how long can i stay in the US .. while looking out for a new job ?

Once you get layoff, you are out of status and must leave the country unless you are able to find another sponsor immediately.

Hi, Do you have a special form to fill out a Withdrawal petition for fiancée, or it is enough only written letter from me?

As Alexander noted, make sure the cover letter clearly state your withdrawal. That should suffice.

That is not an issue as sometimes it may occur. Your work permit is valid.