How do I sync PROD user security & data access to TEST

Summary: Sync PROD user security & data access to TEST

Content (required): I am looking for a way to sync the users, assigned roles and data access in PROD over to TEST. Our managed services partner is telling us the only way to do this is manually. This is incredibly inefficient & would take several hours to complete for over 100 users. Is there an API or spreadsheet loader to do this?

Version (include the version you are using, if applicable): 23B

Code Snippet (add any code snippets that support your topic, if applicable): N/A