WordPress 6.5 Site Editor Template list doesn’t match file manager/ftp client

With modern FSE themes, these files only serve as a basis for the setup. You can set up additional templates or customise existing ones at any time – however, these customisations/additions are saved in the database, not in the file system. Therefore, there are also differences here.

I don’t know why you are even looking at the file structure. This is not necessary when simply editing the templates. Just go to the templates in the editor and customise them as you wish.

Here’s a bit more about templates in block themes: https://www.ads-software.com/documentation/article/template-editor/