Good practice is to activate your new PM sim and start your account. Take a temporary number until your PM account is stabilized and working...then initiate a number port from Fizz to PM.
Make sure to keep your Fizz account active as it can't be ported once you close the old account.
Do some reading (as provided) to get a good idea on what steps are required to port.
Welcome to PM.
added....
https://www.publicmobile.ca/en/bc/get-help/articles/number-transfer-port-troubleshooting
