The life expectancy of someone diagnosed with liver cancer depends on how severe the liver cancer is and how far progressed the liver cancer is.
If you get treatment for the liver cancer then you might be able to live a normal lifespan but if you don't get treatment then you might live 2 years to 5 years after diagnoses of the liver cancer.
The more far advanced the liver cancer the less time you have to live especially if you do not get treatment.
However sadly most cases of liver cancer are inoperable at the time it's diagnosed so you may not be able to be cured of the liver cancer so you may die within around 2 years to 5 years after the diagnoses of liver cancer.
Most people liver up to 5 years from the time they are diagnosed with the liver cancer and others may only live for 1 year to 2 years depending on how bad the liver cancer is.