CasioKid thank you for your answer but is not really what I'm looking for
Mike Martin, Thank you for your answer too;
in the documentation in the link bellow :
https://support.casio.com/storage/en/manual/pdf/EN/008/LKS450_usersguide_EN.pdf
I found this :
page EN 148 :
MIDI In Navigate
Can be used to it possible to
enable use of the NAVIGATE
function that causes Keyboard
Lighting to be controlled by MIDI
IN note messages.
MIDI In Navigate
Off, Listen, Right
Hand Off, Left Hand
Off, Both Hand Off
(Initial Default: Off)
But it didn't works, with my programme I'm able to send a MIDI message for play a note :
send([144, 60, 127])
(144 noteOn, 60 the note number and 127 the velocity)
But the key doesn't light up even with any of the previous setting :/