Permissions control exactly what each user can see and do in Preno. Each user also has a Role (e.g. Housekeeping, Back office) shown in your user list — this is just a label to help you identify who's who at a glance. It doesn't set or change their permissions; you control those separately.
Steps
Go to Settings > User management.
Click the user's name to open their profile.
Under Permissions, click Edit permissions.
Tick or untick permissions in each section, then click Save.
You'll be asked to confirm your password before the change takes effect.
What each section controls
Grid — view and search the booking grid
Bookings — viewing bookings, invoices, guests and notifications; creating and editing bookings; cancelling, deleting and rolling back bookings; refunds; downloading guest and booking lists; revealing stored card numbers; setting custom rates
Rates — viewing and editing rates and dynamic pricing rules
Agents — viewing and managing agents
Housekeeping — accessing the Housekeeping page, updating room statuses, and assigning staff
Reports — accessing the Reports page
Settings — accessing the account Settings page
Note: "Can access the account Settings page" is the permission that lets a user manage other users' accounts and permissions. Only give this to people you'd trust with full control of your property's account.