You can use an Ableton Push in FL Studio. However, you will find that much of its functionality has been dramatically reduced because it is not being synced up to its native Ableton software. When using a Push with FL Studio, you will find that the main screen at the top does not show any of the information that it would generally show if you were using it with Ableton. That being said, you will still be able to use the pads as a regular MIDI device. The Push is explicitly designed to be used with Ableton and is only fully compatible with that software.