Hello,
1) Images of products are displayed on Cart, but not on Checkout, by default. If you want to change it, try to contact the support of WooCommerce.
2) It is how full-width sections created by Elementor works. You can see the similar behavior even on our demos – https://xstore.8theme.com/elementor/demos/headphone/ Speed up the site to make it loads faster – https://xstore.helpscoutdocs.com/article/100-how-to-speed-up-my-website
Regards