Create stable build from development

Good day,

I wanted to understand how I would develop in the development build and then shift my changes to the stable build.

I tried reading documentation and other posts here but am unable to understand it.

as an example, the stable build does not have a lot of files like:
webpack.mix.js
/resources/assets/*

Globally installing an open source language has long been the standard way developers have created their development environment for decades.