Hi. I don't play piano, so this area of questions is not my strength, but I feel confident in saying that BIAB can do what you want, with a little work on your part.

Yes, you can enter notes from piano sheet music into BIAB. The method is somewhat different (and I think, better) than Finale. Also, be aware that, when his music gets more complicated, there are programs that can scan sheet music directly into notation programs, and then that could be moved over to BIAB.

You can transfer data between music programs using a file format called MIDI Format 1. All serious programs support that. A few also support the newer Music XML format, but BIAB does not at this time.

I have to look in BIAB about splitting the piano staff. You could always choose to enter the two hands into different tracks in BIAB, so it would be easy to mute one or the other (or both).

As for playing accompaniment with the melody that would make things more fun, that is the strength and main purpose of BIAB. The catch is, you have to enter the chord symbols so the program understands what to generate as accompaniment. Some piano scores have chord symbols, some do not. If it does not, you would need to find someone who could tell you what the chords are. BIAB does have a utility called Audio Chord Wizard if you have an audio recording of the song, to guess the chords.

I'm sure the keyboard players here may have better ideas.

Also, I note that you are running a test version of Finale. BIAB doesn't have a demo version at the moment, but does have an unconditional 30-day money-back return policy. I don't know anyone who ever returned it, though!

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