Squarespace Calendar Integration

I need help integrating an availability calendar on my Squarespace site for my home maintenance business.

Requirements:
- An availability calendar with time slots
- Customers can view my availability and request to book, but I need to confirm the bookings
- Ability to both manually update my availability and sync with an external calendar

Ideal Skills and Experience:
- Experience with Squarespace
- Familiarity with calendar integration
- Ability to set up manual and automatic syncing with external calendars