Happy day to everyone.

The scenario is the following:

It is a company that sells ads on its website, to be published directly on the same website. The publications are divided into categories, however I do not know how to perform that process.

The process is: Client buys a quota for a publication -> Client mounts his publication -> Client pays the publication -> The publication appears on the website

How can I do to fulfill that flow and be able to sell my service?

I appreciate any help, thank you very much.