How can I create different scrolling speed effects for different sections on the same page using gsap?

So I wish to create a portfolio for myself by using the scrolling effect done here. As you can see, the left content scroll at a slower speed and the right content scroll at a faster speed. How can I archive this scrolling effect (VanillaJs or ReactJS). I tried using gsap scrollTrigger but to no avail. I just want the scrolling effect.

Thank you.