Well, actually, you can leave the next day after landing, if you want to. It's not advisable though.
But to enter Canada again, unless you're travelling by car, you'll need the PR card. So the two options are:
1. ask somebody to get you PR card for you and mail to your current address. This is risky though, because you don't know when your PR card will arrive, and if they would need new photos or something.
2. get a Permanent Resident Travel Document, a document specifically designed for this purpose, you can look it up on IRCC's website.