CMS Gallery multi-image

I am a photographer and have thousands of images spread among a hundred of galleries that I want to post. I know how to post them in the collection template pages but can’t do it in a normal page. Is there a way to use collection template pages as they are? What other options do I have to make a gallery in a similar way that simplifies the process and won’t take a hundred hours?

Here is my public share link: LINK
(how to access public share link)

I am only looking to include 50-75 images per page.