Sorry for the inconvenience. Some tricks need to be done to optimize page speed. So first of all, remove unnecessary pages, posts, post-thumbnails, products and product thumbnails (That you don’t need).
Then use an optimized plugin like https://wordpress.org/plugins/wp-optimize/ WP-Optimize is a revolutionary, all-in-one plugin that cleans your database, compresses your images and caches your site.
Finally, Install a cache plugin like https://wordpress.org/plugins/wp-fastest-cache/
Hopefully following these instructions will improve your site’s performance.
N:B: Read this article for why the website is slow: https://www.bitcatcha.com/blog/10-frustrating-reasons-why-your-website-speed-is-slow/