my friend, since you don't know how to do it online, you better take your time, put everything together then send it to them by usps.

Read this carefully and do it accordingly https://www.uscis.gov/file-online/tips-for-filing-forms-online

I had to send RFE. It was mailed.

on the website. i submitted my rfe online one week after my interview & mailed it. now, I am currently waiting.. it’s been 14 days