Hi @NicGie ,
Thank you for reaching out to us. You can set the numbers as shortcuts for labels/ratings from keyboard shortcut options
1. Open Bridge
2. Go to Edit -> Keyboard Shortcuts to open the keyboard shortcuts dialog
3. Search for the desired command like Red Label, Yellow Label, 1 Star, etc
4. In the adjacent column, named "Shortcut" click in the empty area and add the desired shortcut like 5, 6, 7
5. Save the preset and click the OK button to apply the changes
You can follow this wiki for more information and usage https://helpx.adobe.com/in/bridge/using/keyboard-shortcuts-panel.html
Please reach out to us if you have any queries.
Thanks,
Bridge Team