Here's a page with a few shortcuts Former user (Deleted) found.
https://blog.mbedded.ninja/electronics/general/altium/altium-keyboard-shortcuts/
https://shortcutworld.com/Altium-Designer/win/Altium-Designer_Shortcuts
http://valhalla.altium.com/Learning-Guides/Legacy/GU0104%20Shortcut%20Keys.PDF