I am 19 years old can i help my father with his citizenship.

Unfortunately you will have to wait for your 21st birthday (assuming you're a US Citizen)

Assuming you are a US citizen, you will only be able to sponsor and petition your dad for "green card" status once you become 21 years old. Not before. Also, dad can only apply for a green card if he was previously legally admitted to the US with a visa and passport. Otherwise not.

You must be 21 years old and a U.S. citizen in order to sponsor your father for a green card. He can apply for citizenship after he has been a U.S. permanent resident (green card holder) for 5 years.

Right now no. You need to wait until you become 21. However, your father, if he is in the US, might be eligible for DAPA