Wi-Fi Smart Scale with Direct Connection to Website with ESP8266, Arduino IDE

I would like to make a basic website that will be attached to my existing domain, but eventually its own domain. I would like the website to be a dashboard for adding and viewing wifi smart scales and then running a functions on the data from those smart scales. So a protocol would need to be created for adding smart scales with a unique identifier etc. I think it is also wise for there to be a setup protocol to setup wifi passwords etc. The website should have a user log in process to be able to view their own wifi smart scales. I will be the only user for now, but i wish to scale the website for people to have their own smart scales that they can add. I would like to make a Wifi Smart Scale using the hardware listed in the below link. I just want to modify the code and setup to publish directly to my website, that way i don't need to use external applications etc. My guess is instead of posting the data to Ada Fruit and IFTTT, it will post to a API endpoint or something like that. This will need to be setup [login to view URL] The data is just going to be weight data which is a number. We will need 2 functions created to work with this data. The first will be basic maths based on user inputs that should be saved. The second would be a more advanced function like emailing the calculated amounts form the first function to a user defined email address, but button press AND at a user defined interval (eg. daily at 2am). This second function will later be modified to work with another websites API, so we will need to be able to easily modify this. In your bid, if you can please provide a brief description on how you intend to achieve this and any questions or concerns you might have, that would be great