Their hours
Open the person under Team. Weekly schedule sets their working hours, then Save hours. Until those hours are saved, they use the business hours from Schedule → Availability. Customers only see times that person is actually working.
Time off
On the same profile, Time off & vacations blocks a stretch for that person. Enter a start and an end, then Add. Everyone else keeps taking bookings.
Their services
Assign services to a person from the service, or from their profile under Team. Customers choosing that service see only the people who can perform it.
Their profile
A team member can have a photo and a short description, plus a portfolio of their work, shown to customers when they choose a provider.
When someone leaves
Remove their services so no new bookings are made, move any appointments they still have, and then remove them from the team.