available times for appointments during a specific time range?

I'm creating a registration form for a demonstration. After the demo, there will be time slots people can reserve for a personalized session (I'm an animal communicator). What widget can I use to show a specific time range and will indicate when a specific time slot is taken? Also, I need to add a payment link as well.

Thank you for your time.

-Holli

I see your form already is using the appointment slots widget. And you have a payment integration also. I was going to suggest the same.