newbie72 said:
My study visa is good till Sept 2017, can I still enroll in school?
No - it's not valid. And no - you can't enroll in school.
September 2017 was your original visa's validity. However your study permit was only valid as long as you remained in school as a full time student and met the terms of your study permit.
CIC introduced new rules in 2014 whereby study permits are now automatically canceled once a student drops out of school for more than 90 days. So your study permit is now unfortunately invalid (since you dropped out of school) and you've been in Canada for quite some time now illegally / without status.
When someone goes out of status, it's possible to restore your status provided you do this within 90 days of going out of status (so you would have had to apply to restore your status shortly after dropping out of school). You're well past that being possible. Again, your only option is to leave Canada at this point if you want to be in a position to apply for a work permit (or another study permit).