Your COPR can never expire as this is confirmation of you being a PR of Canada. the PR card allows you to enter Canada if you travel. Otherwise you will require a PR travel document (PRTD) which can only be obtained from the country you are travelling from to Canada and at this time there is no guarantee on the timeline for receiving the PR card and no guarantee that you will get the PRTD from the country you are leaving from (assuming this is India) as the Embassy may be restricted services. I understand that if you have a US visa, you can drive across the land border as a PR providing it is not a cmmercial vehicle like a bus etc.- maybe a rental car and there may be many questions asked by border control. I got my COPR in July and am waiting to travel after I receive the PR card (I am CEC inland).
@legalfalcon please correct me where I may be wrong in my answer