Testimonial Slider Structure Understanding

So we have the Outer layer (GREEN), in which we set it to fixed sizes when in mobile size and desktop size, then we have the actual slider (RED), in which we set it to fixed size for both desktop and mobile, this one is the one that we slide left right? and then we have the cards (PURPLE), do I understand the building blocks of the testimonial slider right? Or any slider in general, is this how they build sliders?