I am going to Nepal in august 23 and have about 20 days. Do u think it is good enough time?

Currently i am working in H1B in university. I have H1b approval notice but dont have labor certification or any other documents with me.

I am little confused about the requirement for H1B visa.
I sent an email to US embassy but seems they dont reply about anything related to VISA.

Could you please give me little more details what i need for H1B visa.

Thanks!