Permission for user to view purchased content

What are some possible options to build the following into my website.

I have multiple students with their own login, let’s call them student 1, 2, 3 & 4. I have multiple content, let’s call them content A, B, C & D.

I need a student to be able to login, add a content option to their shopping cart, purchase it and then have that content visible to them from within their individual student login portal along with any other purchased content.

On the server side I’d like to only use PHP and MySQL.

What is the best way to achieve this?

Thank you.