This is an area of Tropy we want to improve, by making projects more portable; at the moment it is not possible to easily adjust all file paths within Tropy; you would have to adjust each photo individually by right-clicking on the photo, selecting Consolidate Photo and picking the photo from its new location.
Obviously this is not feasible if you’re working with more than just a handful of photos.
Having said that, if you changed the location of your photos in a uniform way (e.g., moved all the photos to a different folder or, as you say, just renamed the folder) it is very easy to fix the paths in your project file with a single database command. I posted detailed instructions in another thread; in your case you would also need to remember the original (or old) path of your photos. One way of doing that would be to open the database file (step 4 in posted instructions) and then issue the following command at the prompt: select path from photos; to print all the paths in currently set in your Tropy project. This would show you what the original path was. You would then issue the update command as described.
You seem to be using macOS where sqlite3 is already installed; if you try this out, please don’t forget to make a backup copy of your project file in case anything goes wrong. Alternatively, I’m happy to make the change for you if you post your project file here (or send it tome at sylvester.keil@gmail.com); additionally I would need to know the full current path to your photos.