Roles in BeeCastle represent an additional set of permissions and features that are enabled when a user is given that role. Each user can be allocated multiple roles, with everyone having the 'user' role.
To understand what each role enables, see this table:
If you are an admin, you can edit your users roles by:
going to Settings -> Users and selecting '...' on the relevant user
Selecting 'Change User Roles'
Selecting or de-selecting the roles to get the prefered role set before selecting 'save preferences'
This will save the role changes and that user will now have access to the features that role enables (they require a page refresh!).