Travelling while waiting on H1B notice

I am currently working on OPT status that is extended due to pending H1B. I need to travel back to Canada. I know there is almost no chance of 2020 H1B approval as I have not received anything in regards to the application.

Lets say I somehow get my H1B approval notice, and I travel to Canada. Would I be able to stay there until my I-20 is updated and all paperwork is sent to my Canadian address. I just dont want to hinder my very very unlikely chance of H1B approval if I am somehow selected.

Once you leave US, it is up to the country you stay to let you stay or not. So, if Canada allows you stay, then you may. Check Canada immigration rules. You will need to go for stamping in Canda, double check with they allow Change of Status from F1 to H1B in Canada.