Copy using Ctrl + insert should be added. Also Shift + Insert and Shift + Delete like what is implemented in Windows.
“Ctrl + C” and “Ctrl + V” (“Command” rather than “Control” on macOS), are pretty well universal shortcuts (Windows, macOS and Linux).
If you prefer “Ctrl + insert”, “Shift + Insert” and “Shift + Delete”, then you can customise the key bindings. See: https://manual.audacityteam.org/man/keyboard_preferences.html