Need help with Azure webapp

Context- i joined a project 2 years back and recently we started working on vulnerabilities. One of which is regarding couple of webapps configure for d365 with public access. As per the recommendation we need to configure private endpoint to mitigate the vulnerabilities.

Problem - nobody knows what these webapps do actually. We have a dedicated d365 team and even they don't know what these webapps are for. And i cannot go ahead and configure a private endpoint without knowing who will provide me with the configuration details. The team also mentioned they dont have any documentation or handover since this was probably configured during the transition period

Can someone help me figure out a way know how these webapp might be used or if its being used at all. Also how do i configure the private endpoint for this without any information. I am new to this and i dont know much about webapps.