Help my sister escape abuse

Six months ago, I moved in with my step mother, my abusive dad, my 15 year old step sister, and my 5 and 6 year old sisters to help babysit when my mom would go to work. The house we lived in had fleas and didn't have a working fridgerator, a kitchen sink, no heat, mildew growing along the walls and floors, and no walking space because of hoarding. The kids grew up with neglect, had to witness abuse and hard drug use all of their childhood, and had to live in a chaotic house with no consistency or discipline. They didn't even have a bed because my dad used his room to smoke crack in, and their room to sleep in. My step mom told me she felt trapped and wanted to leave and save her kids. She didn't have the means or willpower to move out on her own, so we both saved up and got an apartment together. The night before we left, my dad found out and held us hostage with his friend sitting in the driveway all night. He took our phones so we couldn't call the cops, all of our identification, debit cards, and pocket money. He also hit and bit my step mom that night, suffocated me, and threatened to kill one or both of us. I was able to escape the next morning and ran to work and later that day when he left to buy crack, my mom snuck out with the kids and filed a police report. My dad went to jail, we moved out, and everything was fine— until he was released. A few days after my dad got out of jail, my mom was already visiting him behind my back and going back to the situation she said she wanted to leave so badly— with the little girls. She started off with leaving me and my step sister for hours at a time, then days at a time, with no food, clothes, or contact. Eventually she abandoned her 15 year old to go back to a dangerous household. I knew that she would eventually try to take my sister with her, so I took it upon myself to get temporary full custody of her because I promised her that she would never have to live with my dad again. I have court on the 21st of March to petition for full custody until she's an adult. While I'm aware that this is an incredible responsibility, I know that I can do it because man is willing to shoulder any kind of suffering as long as he can find meaning in it. Unfortunately however, all of these things happened in the matter of a month and I did not have time to prepare for it. I really need help getting started. I''m struggling to pay rent, utilities, clothes, and food for this month. Any amount will help. I will do everything in my power to keep my sister safe and in a comfortable home, but DCFS is coming to make sure it's a fit place for a kid to live, and if I fail to provide, she will either have to leave with her mom or be put in an emergency foster home. My sister is the most important person in my life and any help at all will be greatly appreciated. Thank you.