Do you have a type of document you want to open with a specific default application in Fedora? For example, do you want to always open JPG or PNG files in The GIMP, WAV files in Audacity, or SVG files in Inkscape? You can do this and more in the interface of the Files file browser (also known as nautilus) in Fedora via the Properties window.
Right-click on any file of the type you’re interested in. Then select Properties to bring up the file properties. Select the Open With pane, and select the desired app. You can then either open the file this time only with that app, or you can select Set as default to always open with the new app from now on.
Take a look at the demonstration graphic below:
Many apps automatically provide a default assignment like this when installed. However, often file types can be opened by more than one app. Now you can choose the one you prefer.