You do not have to register the booster with the carrier in Canada.Be sure to have a booster that boosts the correct frequencies. Typically a carrier use slightly different frequencies than another carrier. Your best bet is to use one configured spec...
There has to be a signal to boost. You can’t boost no signal to create one. Even one bar can be boosted. But if you don’t have any signal, you’re unfortunately out of luck.This being said, look at the coverage maps. If it shows coverage where you are...