The GFPT allows longer time between check rides with an instructor. Ref CAR 5.70. That's pretty much it when it comes to the difference of a student pilot with or without one.
As for endorsements, it's all there in CAO 40.1.0
GFPT not required for an endorsement. A student coming up for test must be endorsed on the type of aircraft for the test. Quite a few people use CSU aircraft for basic training, for example, and go first solo in them CAR 5.68.
Ratings however are a different matter, a student pilot can do night circuits but that's all they can do where a rating is required. Otherwise you need a PPL to do a rating.
An insurance company may insist on a GFPT but that is a separate issue.
