How do I set up the shopping cart and 3 payment system?

How do I set up the product, shopping cart and 3 payment system?
Technically I am selling nine courses as one "product" for one single payment.
And the same "product" for three monthly payments.
1. My courses are marked as unpaid.
2. Protected Content is activated.
3. How do I set up a paid membership of the 3 payment product?
4. Where do I protect access to my courses as they are currently marked as unpaid.

p.s. Clear and concise step by step instructions with screen prints are very helpful.