4 year old sleep help

Hi, my daughter is 4 and extremely strong willed. We are having a very hard time getting her to bed. She always runs out, refuses to stay in bed. She says she is scared of the dark. I have a nightlight on for her. Currently trying to “sleep train” with the chair. Sitting on the chair while she’s in her bed. Any tips? We are going crazy. Takes her ages to fall asleep! We got rid of her pacifier a month or two ago and sleep became so hard. She also has ADHD like behavior (large tonsils) and wakes up every night once or twice. At around 11, then once more. It’s hell. As if we have a newborn again, but worse. Any tips greatly appreciated!!!