I think once you received your COPR, all your TRV’s and work permits become void.
You’ll be able to travel from Canada. But to return back to Canada you’ll require PRTD. Permanent resident Travel document.
You can either wait for Pr card and then travel once you have your card or travel with COPR and apply for PRTD with your return ticket details. I think it is 75$ for that document.
You can find more details about PRTD in the CIC website