One dentist says I need root canal, another says core buildup and crown with no root canal. Thanks! (Photos)

Do I need a root canal or just a large filling? I am terrified of going to the dentist and put it off for a few years. I had a cleaning done with x-rays and told I need a root canal on my upper left first and second molar. Both teeth have had multiple fillings done and redone to try to create a better contact however there has always been a food trap between these teeth. A new cavity has formed under the filling. Do I need a RC? I have symptoms to cold thay lingers for a few minutes in that area.