Financial help for my 9 year old brother's chemotherapy and other medical expense.

We are greatly in need of financial assistance right now. We are asking for help with my 9-year-old brother. He was suffering from pain above his knee. Due to financial problems, we were not able to bring him to a proper doctor immediately. After 4 months, he was diagnosed with osteosarcoma or bone cancer. He was crying because of the pain so we decided to take the doctor's advice to remove his left leg. Recently he had undergone his first chemotherapy. I am afraid that we were not able to sustain for another chemotherapy and his other medical needs.