Require Advice

I am looking for some advice. My Grandad (73) who has raised me has been diagnosed today with Primary Liver cancer. I am not sure what stage the cancer is at however i know he has been offered chemo as treatment. Hes been poorly since the start of this year. It started with pain in his stomach, then loss of appetite and has increasingly got worse to the point he has stopped eating completely and has no weight on his bones whatsoever. I understand that he is very ill and i know how much chemo can take it out of people. I fear that his body is not going to be strong enough to maintain the treatment and for him to fight infections. I just wondered if anyone could advise on the best way for me to encourage him to eat. Or even ways to take his mind off treatment and what the future holds. He is the center of my universe and i want to be able to support him the best way that i can through this and to be the strong shoulder that my Nan can cry on. Thank you in advance