How far and how high I can fly in F MODE course lock? And what happend if I losse barometar signal? Did phantom than automatic use ATTI MODE or what happend?

You don't lose the 'barometer signal', because it is not a signal, it is a device attached to the aircraft. And you can fly up to 500 Metres and as far as your range will let you.

If the barometer is broken, the drone cannot hold its height.