Role management for employee

What is the maximum number of role i can assign to employees that has no administrative function in an organisation?

If i assign them just “EMPLOYEE” as a role on the role list, will it be enough access for them to be able to apply for leave, apply for employee loan, request for expense claim and utilize other features meant for employee?

Yes. The Employee Role access should be sufficient for them to access HR functionalities.

If you want to check what access the role has, simply go to the role permission manager and select Employee in the role, all the permissions will be displayed:

Or you can just click on the Employee role in the user settings to check: