Renew EAD

I have some question about renew EAD. I really appriciate your help.

1. I just came back from China using AP and I never use my EAD, so currently I am still in H-1B status.

What should I fill the the questions in From 1-765:
#14 Manner of Last entry
#15 Current Immigration Status
#16 Eligibility under 8 CFR 274a.12

2. I read the instruction for I-765, in the beginning, it said: Write you name and Alien Registration Number (A#) if any, at the top of each sheet of paper and indicate the part and number of the item to which the answer refers. What do you do about that? I am confused.

3. I am in Texas, should I mail to
USCIS
Texas Service Center
P.O. Box 851041
Mesquite, TX 75158

Thanks a lot.