Advice please: No-code web platform that facilitates sibscriptions and purchase of time-limited software licences?

I'm a C# developer who is in the process of building a website to sell software I've written. The software includes a licence key which embodies the customer ID, a date range and the MAC number of a computer. Hence it is not transferable between customers, machines and time limited.

I'm looking to build a no-code website that allows me to setup renewable subscriptions to software, on a monthly and annual basis, whereby the act of purchasing the subscription will run an API that I've written so I can email the licence key to the user. I'd also like to be able to access, as data, the underlying list of subscriptions and user details.

I've spent some time bashing about with HTML, PHP, MySQL to know that it's not my forte, and I'd rather not re-invent the wheel. I know that wix and squarespace will not enable me to do this. Does anyone know of a development system that will?