Each person on your team has a staff card under Staff, with their hours and the services they do. Choose Invite to log in and they get an email with a link. Opening it, they pick a password, and that is their login on the website and in the FullDiary app. The invite is valid for 7 days.
If they forget it, Forgot your password on the login page sends them a link to choose a new one.
A staff login sees the diary and can manage appointments - book, move, cancel, mark done - but does not see your business settings, billing or documents. Customers can pick their favourite person when they book, and each member gets an email about their own day.
Remove a login from the same staff card when someone leaves; their appointments stay in the diary.
Add more people than your plan covers and the extra ones are parked - in your list, not bookable, not invitable - until you upgrade. Bring them on from the People section once your plan covers them.