You are not really providing any information for people to help you.
But if you are out of status you will need to do restoration which does mean you cant study/work until they reach a decision, and restoration takes a long time so you will probably miss at least one semester if the sp is eventually granted. This probably also makes you ineligible for pgwp.
Reason on letter was- [X] immigration legislation requires that an application for a student permit be accompanied by a letter from university accepting the applicant to attend or to take any course at that institution. The letter should be recently issued and should outline the
1. Type of course you are registered for
2. Start and completion date
3. Whether program is full time or part time
As you have not provided such evidence your application cannot be approved
The previous app is closed. You need to apply for Restoration. You need to defer until next semester. Do not study or work until you have valid status.