Create appointment types manually or sync your store products/services and assign them to a calendar. The sync method is also the only way to ensure that you setup scheduling alongside your products for payment through checkout. Don't need to collect payment or haven't setup your "services" as products? Use the manual method.
Here we look at the sync method. The first thing we do is use the toggle to "Allow scheduling"
Once done you'll want to use the "Create" button in the popup to create the new type and assign it to a calendar. Here we created the "Dog Yoga Class" and assigned it to the "Class" calendar