Simplest way to run a python application the receives data from a web application, processes/manipulates it then pushes it back to the front end

Goal: A frontend that receives a twitter username that is sent to a python script that then scrapes that users timeline (https://twitter.com/username) then simulates text with that user's tweets using Markov Chains. Finally, this output is returned to the front end.

I don't need help with the actual python coding or frontend. I am just lost on how to "actually start working on this", specifically as to what tools to use to execute python scripts and use these in conjunction with a frontend (preferably reactjs).

Thank you so much for your time and advice