Adding Descriptions to Photo Attachment pages

I am wondering how to add descriptions and alternate text on the image attachment page.

The website is https://www.thecrowsneststudio.com/

I have tried multiple coding blocks to add this feature, and often they will work great in preview but fail once I hit “save” or “update”. For a specific example, if you go to the page below and click on the image “Connie”:

https://www.thecrowsneststudio.com/artists/196-2/art-of-vivian-e-browne/vivian-e-browne-1950s/

You are taken to this page:

https://www.thecrowsneststudio.com/artists/196-2/art-of-vivian-e-browne/vivian-e-browne-oil-and-acrylic/connie-by-vivian-e-browne/

On that page, I would like the bold text above the image to read “Connie by Vivian E. Browne”, and have small text below the image that says, “Oil on Canvas, 35″x29″”. That information is updated in the proper places on the “Edit Media” page, yet won’t display or even update.

Any help is very much appreciated – I’ve tried multiple blocks of code from other asks in this forum, but as previously stated, none of them stick once I save them.

I hope this was descriptive enough – thank you!