If your boss allow you to do, and he give you the company

information, also, he will give the signature. Yes, you can . But it dose not mean you can make decision about the prevailing wage, you must get it from the SWA or DOL website.

For the AOS, after you use EAD(Employment Authorization Document), you will be AOS. But right now, you said you are applying for H1b, I think it is extension of your H1b.