If you want to check access or licence of any user with in power platform or dynamics 365, please use Access Check Tool, using this you can validate user permissions for specific app(s),
You can open access check tool, by putting following URL in the browser.
https://<<ORGNAME>>/WebResources/msdyn_AppAccessChecker.html (replace your organization name
then enter user email address or user id in search box and press search and system will show all the apps user have access to and licence for each app in relevant power platform environment.
This tool can only be accessed if you are system administrator or system customizer on relevant power platform environment.