I will help you create a web services with Python Flask or Python Requests libraries, I've also done a lot of web services using .NET Web API. This includes basic CRUD operations or also authentication services if needed such as providing OAuth2 services or OAuth2 clients.
I can also convert existing application functionality into a web service if needed. A lot of times I get these kind of requests where customers like a git repo available online as a script but not available as a web service.
As far as return data types, I can offer JSON or XML.
Please be sure to message me to find out what your requirements are.
Creation of 1 web service
This includes 1-2 routes for your web service in Python or .NET