I think people are not sure what you mean. If you want to add squares to the homepage/frontpage then try going to – settings>reading then set “Blog pages show at most” to add more squares/thumbnails/photos to the home/front page.
If that does not add them then maybe you have to have the photo set as the “featured” image for each post/entry. Featured images should show on the post add-new/edit page almost always found on the bottom of the right side bar.
If you dont see it then at the top click the tab (top right) that says “Screen Options” and check “Featured Image” to get it to show in the sidebar. As far as I know you dont need another plugin for galleries.
You can add a gallery to a post by using the photo uploader to upload all the photos. It should show a “Gallery” tab on top of that same uploader. You can put the photos in any order you want and choose how many columns you want to put them in. This is for a post not the home page. Unless you choose that post to be your homepage.
I hope this helps but I am not sure if I answered your question but it may help some. Not sure if you want to add the square thumbnail photos to home page or a gallery in a post…2 different things…lol
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