I am giving a presentation in my college where hill cipher is a part of the presentation. I just wanted to know, how is the hill cipher key matrix is exchanged securely in order to decrypt the message?
In the Hill cipher, like in any symmetric cipher, it is assumed that both parties have the same secret key already.
Securely exchanging a key is not part of the symmetric algorithm, neither is it its job. That a separate protocol that needs to be done beforehand.