How can I get the permission descriptions of service principal appRoleAssignment based on it's appRoleId or all the list of existing permissions?

I've found this

Graph API:

Step 2 : Now take each roleDefinationID separately to get the AssignedRole's Name. Using this MS Graph API.

Refernce : https://docs.microsoft.com/en-us/graph/api/unifiedroledefinition-get?view=graph-rest-beta&tabs=http