#1. You can use this plugin, but you have to modify the css so that it doesn’t affect the layout.
We do not support this plugin, so you will either have to customize the code yourself or we will support you for a fee.
#5.1 The link you sent does not check the page you mentioned, so please check the demo again and send me the correct link.
Link demo: https://demo.leebrosus.com/kosi/
#6. This error is caused by your Google Listings and Ads plugin not being compatible with the current PHP version