There is no special health insurance for first time immigrants. The regular health insurance covers visits to the doctor and specialists as well as hospital stay and surgeries if you need them. It does not cover ambulance service, medication or dental work.
You can get instant coverage in many provinces if you are arriving from a foreign country but in some you still have to wait for 3 months before you are covered. If you want instant coverage, do not settle in ON, Quebec or BC.