Develop my website with a dashboard and intergrate an API with my provider to provide product to my customers

I will need a dashboard where each customers will need to create an account. This account will create a sub-users category into my providers portal (using API). The dashboard will have to contain a store where product can be bought (each purchase will change the sub users setup into my provider portal with the API); a data checker, and a function to generate the product ( the product will be generated in my provider portal by API).