Thunar file manager has a feature to add custom actions to file menu and context menu. You can set up them with GUI
Edit->Configure custom actions... For example, you can use “Terminal” to open default terminal emulator in the current directory. File managers often have “F4” keyboard shortcut for that action. Unfortunately Thunar has no option to add keyboard shortcuts for custom actions. Nevertheless, you can do that by editing a config file.
First you should learn
unique-id for that custom action. Open file
~/.config/Thunar/uca.xml with a text editor and copy to clipboard
unique-id from appropriate section, say, “Terminal”, something like
1489564838678107-5. Then open file
~/.config/Thunar/accels.scm with a text editor and find a string with that
unique-id number, something like
; (gtk_accel_path "<Actions>/ThunarActions/uca-action-1489564838678107-5" "")
; to uncomment it and add your key between the last quotation marks:
(gtk_accel_path "<Actions>/ThunarActions/uca-action-1489564838678107-5" "F4")
Save it. If you run Xfce, then logout and login again, otherwise just close Thunar and open it again. Now you have that shortcut.