The PMCF plan is needed per EU MDR 2017/745. But before having a PMCF plan, a Clinical Evaluation Report should be provided. The PMCF is helping you to gather clinical data when your device that is already CE marked is used per indication. These data should prove that your device is still safe and efficient.
You need to have a Technical File and Clinical Evaluation Report to be able to complete some of the elements of this template.
You can also buy the Bundle Tech File + GSPR + DoC to help you.