IF you receive the COPR, then you are a PR and you need a PRTD to re-enter Canada. The info provided to you is correct.
Ideally, if you were not physically in Canada, you should not have received an e-COPR. Since you did, you now need a PRTD or a PR Card to enter canada.
Thanks, @legalfalcon for answering
Just another silly question I have is as the PRTD application is taking months, what will happen if I travel with my TRV?
The airline just check the visa and they (might)will allow but what will happen when I reach the Canadian airport?
Thanks