Cirrhosis??.. Help please..?

I overheard my aunt talking to my mom.. I just found out my dad is sick.. I heard the word cirrhosis and stage 1..I don't understand. is that a type of liver cancer?? i've searched through google but they're not making sense.. it could just be me, my my english knowledge is being compromised due to panic attack!.. can someone explain it in simple words? is this reversible? i'm still just a kid, can I be a donor to my dad? we can still stop it right?