real case of my room mate:
1. Finished studies in Aug 2019
2. Applied for PGWP in Nov 2019
3. Refused end of Jan 2020
4. Applied for restoration and PGWP in April 2020
5. Got approved in May 2020
If the study permit has expired, then it is usually 90 days time you get to apply for restoration of status. You should hurry since you need a PGWP. Due to COVID-19, you now have time until Aug 31, 2021, to restore. Check the announcement and instructions on the cic website,
https://www.canada.ca/en/immigration-refugees-citizenship/services/coronavirus-covid19/restoration-extension-trv.html
You have to restore your status to a study permit and apply for PGWP in the same application. You have to pay the work permit fee, ($255) + study permit ($150) + restoration ($200). When you apply online and upload your documents, you will be able to pay the work permit fee but there is no option to pay the restoration + study permit fee ($350). You should make that payment separately and upload the receipt under Client info. He did take help from a consultant because there were issues with the duration of his studies. He failed and college didn't allow him to continue. He then changed college so all this needed to be explained. Yours is a simple case so research on the CIC website and apply for restoration, incase the call to IRCC does not work for you. Good Luck!