Don't worry! Everything will be ok
If your gf is pregnant already I would recommend looking for a midwife as soon as possible according to your postal code(they are very strict about jurisdiction), here is the link- https://www.aommembersonly.ca/find_a_midwife_iframe/Search.aspx
It is possible that she will be waitlisted as they book up very very quickly but they also free up quickly when some women have to be transferred to an OB for high-risk pregnancies etc.
There is a midwifery practice in Etobicoke that helps a lot of women who give birth as visitors, it's called Midwife Alliance. They also gave me the name of a clinic that has OBs that help people with no OHIP but I can't remember what it's called, sorry!
If you are a PR or Canadian then your child will have OHIP, usually what causes huge bills to accumulate is the time that non-OHIP babies spend in the ICU, that is very expensive if both parents don't have OHIP.
Send me a message if you have any further questions! I was in your shoes not too long ago and would have appreciated meeting someone who had been through it before me