Pages word pro file cannot delete just one page

You can delete a single page in the Thumbnails panel. But before that, you'll need to isolate that single page into a section of its own. Please follow the steps below.

Step 1: Click after the last text on the page above the one you want to delete. Then, go to the Insert menu and choose Section Break.

Step 2: Click after the last text on the page that you want to delete. Then, go to the Insert menu and choose Section Break.

Step 3: Click to select the thumbnail for the new single page section you have just created, and try to delete it.

You said that you've already made sections, but you still couldn't select a single page. It's possible that the section break was inserted at an incorrect location. You can refer to the method above and try again. Hope this can help you.

In a word processing style Pages document, you cannot remove a page via the thumbnails. Enable View menu > Show Invisibles and then manually select the content on the page you want to remove and delete that content with a backspace. Then, on that blank page, you perform another backspace to remove the page break.

In a Pages page layout style document, every thumbnail is a page and a section. Thus, you can remove a page by clicking on the thumbnail you wish to remove and selecting delete without it altering the rest of the document.

In either document style approach, it is wise to have the document backed up by Time Machine so that you can recover it if necessary.