How to add piano notes?

How do I add my own piano notes?
I tried opening a second track, but still not sure how to change the input to piano.
Do I have to download something?
Currently I have a background music uploaded, but it would be nice if I could create one myself instead.

You can’t… It’s a vocal synthesizer, not a DAW.

If you’re talking about creating your own compositions, you need an external program like FL Studio

Thanks corasundae and FasheX