Deactivating JS script for mobile screen size

Hi there!

I'm currently working on my own portfolio website. I'm a beginner when it comes to coding, so that's why I need some help. There will be various things to be fixed, but for the moment I need someone to help me deactive a JS script when the browser window is smaller than 600 px.
What's important to know: I'm using a JS library called fullpage.js for all screens larger than 600px. For the mobile versions this should turn off, so that all the pictures are displayed one on top of each other with a 10px margin.

Here's one of the pages: http://cedric-widmer.com/AFRICA.html

I'm looking for someone who can help me out with other things too in the future.

Looking forward to hearing from you.

Best regards,

Cédric