Maybe I don't understand the question. If you want to transpose the piece so the Bb becomes a C, you will have to move all the chords and all the notes up two half steps. What do you mean "is still included in the music"?
What key is the music in? Jim's right. Just move it up a whole step. Or slap a Low G on your uke and play it the way it's written.
It is in Bb
I have transposed to C but it is still in the music .
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Is your question about the use of software, or about music theory? If it's the software, please tell us what you are using and maybe someone can help. I'm a Luddite who uses pencil and paper, so that someone won't be me!
The lyrics in this image do not match the one above, so now I'm really confused by what you are asking. The lowest note shown in this image is A below middle C, so perhaps instead of going up, you went the other way?