How to find keyboard buttons while sitting seat?

Sorry for the unclear title. I have a script in a seat of a flying vehicle that make it move by finding the throttle,speed and steer values, the thing is i want that when the player sits on the seat he can use Q and E for another movement, so how can i make the script find the player and know when he player press buttons?

ill try to explain it another way to make sure everyone understand what i mean:

If player hold Q then bla bla bla end

Oh and i would like the same thing for the left mouse button if its possible

Thank you for your time, Paldi.