FL Studio for Windows does not yet support generic MIDI over Bluetooth as used by devices such as Jamstik, Roli Seaboard, etc. This is mainly because MIDI over Bluetooth uses a new API that is exclusive to Windows 10, we have yet to integrate it with FL Studio at this point in time.
MIDI controllers which support MIDI over Bluetooth through their own device drivers rather than generic MIDI over Bluetooth should work with FL Studio. In these cases, MIDI Setup instructions are the same as for MIDI controllers connected via USB.
Image-Line Support Team