What is the process of compiling .less files with the Gulp builder if the files are on the server?

Question

gulp.js

I'm just getting into the front end for now, so sorry for the stupid questions.
Projects are handled via FTP. I figured out how to compile less locally using Gulp.
But now I want to work with real projects and I can't understand the organization of the process via FTP.
After reading in Google, I realized that in order to create a Gulp project, you first need to install the project locally, and then upload the modified project back and, as I understand it, only the modified files from the project will be uploaded.
I would like to know from knowledgeable people.