1. You have way too many posts showing on your main page, and with it being image heavy, it takes forever to load on my wireless internet connection. Go to settings > reading and decrease the number of posts to show on a page to something like 3 or 5 at maximum.
2. As Timethief says, CSS is theme specific which means what works for one is highly unlikely to be the solution for another.
3. With modularity lite, the stuff below the posts is an all or nothing proposition since all of the elements are under one single selector in the CSS. The theme designer did not separate them out. That means hiding one hides them all, including the date and the leave a comment link. The following hides them all.
.postmetadata {display:none; }