They are telling you what you have to improve/change in your site, we would have to see your site to be able to help you, but with the information we have this is what I can tell you:
1. Improve the loading speed. Here are several things that can be:
-Switch to a better server/hosting.
-You may have a lot of images, plugins... that make your site load slow.
2.Create navigation:
-Offer a more orderly navigation so that people who come to your site can clearly see what you do, who you are, contact...
3.Improve the content of your site:
-Google wants people to get to a site with good content if they come from their ads, so it does not serve you a site of the type... Leave me your email and I'll tell you more.
-With Google Grants you can´t sell, you can´t have ads of other brands/offers...
Tip: read the Google Grant policies and you will know better how it all works.