The links above are full of good information for both you and your children.
Hospitals and hospices are there for you and your family as well. Social workers are available to help you navigate through the process, offer support, find resources and discuss 1 on 1 with you, your father and the family.
Look through the resources. I'm sure they will be of assistance to you.
I remember when my Dad was told he had 2 months to live. I felt so sad and could not focus either. I felt like I was walking on eggshells waiting and not knowing what to do. I'm so glad you are reaching out for information to help you get through this. ACH2015 has given some great resources.
My family took it one day at a time. We sat down with my Dad to talk about what was important to him. This gave us peace of mind to know we were carrying on as he wanted. He told us to visit as much as we could but encouraged us to carry on with the day to day. He would keep us posted on how he was doing and as things got worse we could reevaluate what we needed to do. My kids were much younger at the time almost 4 and 1. The 4 years old was very aware that Papa was sick and she did eventually ask me if he was going to die. I was honest with her and I think it helped prepare her.
Every family and situation is different. Listen to your heart and talk to your Dad to figure out what will help you cope going forward. One thing is for sure talking to other people who understood really helped. Please know that if you ever want to talk I'm here.