Read the readme. If you want to use a real ms-dos from within DOSBox you need to boot a ms-dos disk image.

Hint -> boot & imgmount commands.

Ok got it. Thanks ofr advice 😉

You could also run 4DOS inside DOSBox, that should give you enough options for changing the prompt (;

Yup, 4DOS FTW.

http://www.4dos.hit.bg/

I've seen a game script which utilizes prompt to ask a question.
Except a visual change, it remains fully functional in dosbox.
Something like

1echo Do you want to start a game now? (type Y or N)
2prompt ?

Of course Y.bat and N.bat are in the same directory 🙄

For the implementation of prompt command, there is function.patch that provides such feature on sourceforge page.