A cloud-based identity and access management service for securing user authentication and resource access
The roles in Purview are specific to the RBAC needed within Purview and not necessarily the same as the Entra Directory Roles:
https://learn.microsoft.com/en-us/purview/purview-permissions
The roles in the Purview Center that are also Entra roles are listed in that doc:
https://learn.microsoft.com/en-us/purview/purview-permissions#azure-roles-in-the-purview-portal
So to your question, it depends :)
If you need to leverage PIM for a Purview role group, you can do that following this:
https://learn.microsoft.com/en-us/defender-office-365/pim-in-mdo-configure
Note this however:
https://learn.microsoft.com/en-us/purview/purview-portal#permissions-and-subscriptions