How to add buttons for book covers similar to Homepage

Site URL: https://authorjustbae.com

Hi guys and gals. I'm not proficient in code and need your help. On the front page, I've listed my books using the Gallery for display and clickable to an URL. What I want to do is create a new page and list the titles how they are on the front page but add buttons underneath each book cover  that states "Available at all retailers" or similar. I've tried different scenarios using the product image page but it only gives me three at a time and the buttons are aligned to the left which is weird. There's no way to align them centered (Check my page section "Hot and Spicy Romance Novels..."). I prefer to have the gallery like on the front page but each book has a button underneath. I believe I'm on 7.1 but no sure. I surely need your help and thanks!

To align center button, add this to Home > design > Custom CSS

div#page-section-5f35a6b7654e9d7333c1e607 .image-block-card-text-alignment-left .sqs-block-image .design-layout-card .image-card>* {
    text-align: center !important;
}

So I inserted the code @tuanphan but on the Mobile Version on my page where it starts "Hot and spicy romance novels now on Kindle Unlimited.", it's still showing left aligned for the blurb and button text. Here's the screenshot and check below the picture.

@tuanphanthanks for your help. I figured that out. It was actually in the dashboard under image block. Now, that is done, what to do about getting the buttons on more than three products to be set up on a separate page like a gallery on my homepage?