Congenital heart disease at er

I am now a first-year pediatric resident. Today, a child came to the emergency room and was diagnosed with left hypoplastic heart disease . Because I am a first-year and the hospital in which I am training, medical education is weak, so I was in a bad situation, but the matter was remedied. The senior came to help me, and the problem was dealt with, but After several hours, he died, I don't want this to happen to me again I want a source from which I can learn how to deal with such situations.