Can we travel to india after submitting the PR portal and still waiting for ECOPR ?

You can travel.. once your PR is approved you will get an email asking you to confirm if you are within Canada. You will get ECOPR once you confirm, if you are not in the country your ECOPR will be on hold till you confirm to IRCC with your presence.

as soon as you get an e copr , your TRV is invalid .