Prevent access to a site from a server

I am actually in internship and have an app to create for my structure. It will be an intern app which will allow crud dashboard actions with some data provided by the use of an API of one of the structure partner and make a correspondance to data contained in a private database. Since it's an intern app, I thought about Electron.js for a desktop app because I did a lot of web with Laravel and the structure goes more for desktop app. But it will be my first occasion working with this tech if I choose this solution. Otherwise I'll will go for a web app with Laravel.

My main question is, in case I choose a web app, what can I do about the access issue. Are there some things to do allow access only to the structure members ?

Thanks