I just wanted to wish you good luck!
I am also just starting out. I weigh approximately 345 lbs at 5'4. I have struggled with my weight since childhood also, and live a sendentary lifestyle. My knees and back have given me grief since I was a child and now I walk with a cane. Nobody can attribute it to much other than some minor arthritis and also I am knock-kneed (opposite of bowlegged). However, I don't struggle with near the amount physical issues that you are dealing with. I was very happy to see your message. It gave me hope!
I look forward to hearing more of your journey!