I need help with a command, I've already a few experience in modding, but i've never tryied to do such thing.

Is there any way that make a ground unit fly, like the CommandCenter (the lift off and Land Buttons)?

Please, I need help, I've triyed everything I could, but it still not working, I don't if this is just impossible or if I'm doing something wrong.

Try flagging it as liftable in DatEdit/PyDAT and giving it lift/land buttons in Firegraft. If that doesn't work, you could use a Siege Tank or unit morphing. (Apparently if you unflag a unit as organic it won't be healed when morphed.)