Tabs are a jumble

I’m new to WP, my site was created by a pro. My knowledge of code is copying what is already there.

The films listed on my site — https://www.florentinefilms.com/sherman — have two tabs – About the Film and Donate. I’ve added a third tab to one listing called Press. It includes cleared photos for press outlets to use when writing a story.

My problem is the press photo page is showing outside the borders of the About page, and is combining with the Donate page.

here’s the code for the About page:

<img class="size-large wp-image-3588 aligncenter" alt="IsraeliCuisine Overview-pg1" src="https://www.florentinefilms.com/sherman/wp-content/uploads/2012/05/IsraeliCuisine-Overview-pg1-791x1024.jpg" width="791" height="1024" />
<div></div>

?

here’s the code for the copy and first photo for the first photo:
<img class="size-large wp-image-3588 aligncenter" alt="Israel research trip, most photos by Dorothy Kalins" src="https://www.florentinefilms.com/sherman/wp-content/uploads/2012/05/Israel-6-2013230-Version-2-1024x718.jpg" width="1024" height="718" />

[Please post code & markup between backticks or use the code button. Your posted code may now have been permanently damaged by the forum’s parser.]

finally, is there a maximum number of photos or file size (i’m loading jpegs)? I inserted about ten photos, they appeared, then all but 3 disappeared.

thanks!
Roger