1/ XStore studio allows import sections from different demos, when you are using Elementor plugin. As I can see, you have WPBakery plugin activated on your site, so the Studio can’t be used. Do not enable Elementor, because using 2 page editors may cause a mess in pages content. Footer from what demo version do you want to get? Enable WPBakery for static blocks – https://xstore.helpscoutdocs.com/article/101-wpbakery-page-builder , provide temporary wp-admin access and I will be able to add the Footer static block on your site.
2/ WooCommerce > Settings > Products > Shop page > select page
