can i apply EB2/EB3 on my own?

Hey I am in H1B VISA from last 3 years,I want to apply EB2/EB3 using a petitioner, can you guys let me know what are the document uscis is going to ask related to my current it really possible to apply EB3 without employers given paper, I dont know whether any paper is needed from employer, as i want to higher a petitioner and apply for it,.

Fundamentally, a Legal Permanent Residency by an American Employer (Green Card) is EMPLOYER owned/sponsored. You can not do it for yourself.

At least PERM labor and i140 MUST have a sponsoring employer.