Does Squarespace support image heavy pages?

I am building a site with lot of images on different portfolio pages. I will use 7.1 version.

I am worried if Squarespace will support this? I was hoping squarespace will have a solution and I reached out to them, but it looks like I have to find my own code snippet and add to the site. This code will not be supported by squarespace. I believe embedding for example a lazyloader is not supported in the basic plan. Please correct me if I am wrong.

They did talk about Ajax loading that is part of squarespace but ajax loading is caching common elements like header and footer on all pages. I was looking for solutions like lazy loaders being available for customers.  I dont know code so am looking for easy solutions to use. 

If I dont find a solution to this problem this maybe a dealbreaker for using squarespace. SQspace should support people building galleries of photos on individual pages or pages that are very long and have many pictures. 

Any guidance on this matter from other users or squarespace would be appreciated. 

Thanks