How do I add purchase details under Order Confirmation email?

How do I add purchase details under Order Confirmation email?

I could see an Invoice Notification template, but in the email content how can i add more fields related to the order. I dont see those fields listed under 'Insert placeholders'. I want to add fields like product information, quanity, price etc.

Also how do i create custom email notification like Order Dispatched etc. I dont see that option.