@newuser01012022 (it doesn't like me quoting for some reason?!)
P2 is not an email you need to reply to, rather they provide access to the PR portal where you submit the documents.
When/if you receive access to the PR portal (P2) then you will need to upload another photo. The requirements for this photo are different to the photo you might of used for the initial application and need to be taken by a professional photographer. If in Canada that basically means go to London Drugs, Staples etc and pay your $20 for the picture. The photo is uploaded digitally in the portal (either a scan of the original, or you can use a direct digital photo if you have one).
The process is pretty clear once you have portal access. The online guidance online from IRCC is fairly clear that you should NOT create your own PR portal account if you are a CEC inland application btw, so you need to wait until they supply you with login credentials.