Test environment for SharePoint 2016 Js Rest Api and requestdigest

[SerdarARIKAN]

My company uses SharePoint 2016 on its intranet system. There is a very strict security tightening on this system. It is not possible for me to do development. However, I was assured that the application I wrote could be transferred to the intranet network provided that the development process was done on another network.

I tried to set up a virtual test environment on my own computer, but it is very tedious and there is a 180-day trial period.

What I want to do is to write a REST API application that will run on SharePoint 2016 via html+css+js files that I will put in my own sharepoint area. This application will manipulate (CRUD) the site resources, lists and files in my area. I will use the REQUESTDIGEST security system. As you can see, I need a test environment.

Am I in the right place?