The website is really slow. You got images which are 3700px in width and 1.2mb large on the landing page. You should resize them to the width you really need, probably 1000px in width max. Use .png for images which are transparent and .jpg for images which are not. Also don't forget to compress them. Google Chromes Lighthouse shows an optimization of 16seconds on 4G mobile by resizing/compressing images alone.