I think you've misunderstood a bit how BIAB works, though hopefully we can get a good outcome fairly quickly.

BIAB dos not create accompaniment from the melody, it creates it from the chord progression that you enter on the chord sheet. Whether that's OK or a concern probably depends upon whether you understand chord progressions, and/or how quickly you can learn them.

I like Henry Clarke's videos on using BIAB, as I think he describes things more from a user's perspective than from the manufacturer's perspective: His YouTube channel is here . PG Music's tutorials are on the Support->Videos page and this one may help Making a Song in Band-in-a-Box®

If chord progressions are a complete mystery, say so and it's very likely that someone will try to point you in a useful direction.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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