Where do I start with payment due date, and checking out the plans?

Hello all, so my 90 days are up very soon, however I've read a few times on this sub that people on Nelnet got a 30 day extension. Where on the website do I check if I also received the 30 days? Secondly since I don't know for sure if I did get the 30 day extension I need to start looking at repayment plans. Where do I go to check them and what information of mine do I need on hand? My apologies for asking and making a dedicated post since I'm sure if I browsed on here long enough I might be able to find all this information however I hope making a post will be faster.