here are all of the swiper methods:
https://swiperjs.com/swiper-api
you can just look at the code of his website, he used this js
<script>
jQuery(document).on("click", ".carouselbutton", function(e){
e.preventDefault();
e.stopPropagation();
var $carousel = jQuery(".lay-carousel-wrap").first();
if( $carousel.length > 0 ) {
var mySwiper = $carousel.data('myswiper');
// index, speed
var currentIndex = mySwiper.activeIndex - mySwiper.loopedSlides;
var goToStart = 0;
if(currentIndex > mySwiper.loopedSlides / 2) {
goToStart = mySwiper.loopedSlides;
}
mySwiper.slideToLoop(goToStart, 2000, 'easeInOutExpo');
}
});
</script>
