Xcode change Command+click to Control+click

For Xcode only , you can't change Command + Click to Control + Click.

If you want to change your MAC Shortcut Key then you can Change it from Goto System Preference -> Keyboard -> Modify Keys then update your shortcut key according to your preference.

Go to Xcode->Preference->Key Bindings, search for Jump to Definition. Update the shortcut key according to your preference.