Here’s a step by step instruction.
1.) Go to Dashboard > Pages > All Pages.
2.) Look for the “General Purpose Cleaning” page. (the one you’ve linked)
3.) Edit the page.
4.) On the Block Editor UI, find the Grid Block that contains the images with the text you want to remove.
5.) Once found, click that image block.
6.) Click it’s text (the figcaption). It should look something like this. https://share.getcloudapp.com/jkuLK88r
7.) Remove it.
8.) Do it for all the other images with caption that you want to remove.