To suggest an alternative, have you tried
screen. The thing you are wanting is to change the line disciplne, it sounds like you are in raw mode (each character sent to remote) instead of buffered (or cooked) mode (cr triggers buffer to be sent). there is also a half way house semi-cooked mode (cbreak).
All these values can be set using the
stty command, however it is possible that
kermit will override them when it initialises, unless you cater for that.
Then you want ^? (DEL) to be the delete character. There is a section about this in the Kermit documentation. here. Which explains how to set rudimentary terminal profile for
So I would suggest using
minicom, but this might be impossible due to the remote device's transfer protocol. If you have further information then edit your original question, unless it really is a comment.
Note when you use stty it is the input you set to the serial device not the output
stty [options] </dev/sttyN (since it wants to display output on your screen).