Also posted in r/Advice

Hey guys, this is gonna be a bit of a long post, but I need an outside perspective for it.
My grandma has stage 4 lung cancer, and the hospital we go to has decided to stop treatment and is now focusing on pain management as the tumor has grown through her ribcage. With this happening, there has been a variety of issues that have cropped up. The biggest is the fact that with my grandma's death, my father and I lose our place to live, and while I have friends and family I can stay with, many will not let him into the home due to him being a drug addict and a repeat felon. He is also disabled due to a car accident about a year ago.
My grandma decided years ago that she would get a life insurance plan, and all of it is left to me. This is mostly due to his addiction and him overall being bad with money, I am the one to handle it. My grandma asked me to do several things though, and one of them was that when she dies that I help take care of my dad. My dad is deciding to move from the state we live in, and with half of the life insurance money, buy 2 houses, one of which is in New York. He wants to rent that one out, and use the income to live off of in a state with a lower price of living. I think that this overall is a horrible idea, as he isn't good with money, but neither of us really know how to do anything related to that. I want to rent an apartment in my city for a year, save some of the money to live off of while I go to college, help him get clean and put his life together, and invest the rest so that I have something to fall back on. Most of the family think that both of these are horrible ideas, and think that I shouldn't bother supporting my dad as it is too much of a burden on me mentally, especially as if he doesn't get clean I plan to kick him out of my apartment. I want to help him get his life together, especially since I have a little sister that loves him to death but can't live with us due to him. What should I do in this situation, and is there anything else I can do that I haven't thought of.