How Do I Link FL Studio to Synthesia?

[Buzzed Lightyear]

Sorry if this is a "newbie" question, but to be honest I am quite the n00b. So anyways, I have composed a piano song using FL Keys; and I want to have it played back in Synthesia for presentation. I heard you can link FL Studio to Synthesia using a program called "LoopBe1". Could anyone give me a guide as to how I might go about achieving this?

Huge thanks!

==========================================EDIT=========================================

Going back and reading my post, it seems somewhat ambiguous as to what I want to do. So here's a little more information.

I have composed a piano song using FL Keys.
I have exported the song as a MIDI file.
I want Synthesia to play the MIDI file. (more info on Synthesia https://www.synthesiagame.com/)
Synthesia by default uses the Microsoft GS Wavetable Synth. I do not like the sound of the Microsoft GS Wavetable Synth.
I want to link Synthesia to FL Studio using the program LoopBe1.
This can be done by making LoopBe1 an output device in Synthesia, and making LoopBe1 an input device in FL Studio.
I've done this, but I don't know how to link my VST (FL Keys) to a track. That is the part I need help with.

Thank you for any help.

[Buzzed Lightyear]

Oh, almost forgot. Information about LoopBe1 ca...