Suggested Diet For Muay Thai Boxing Training

Hi, I am a 17 year old student, I have been going to the gym for an hour a week for the last couple of months and from next week I will be starting Muay Thai Boxing, I will begin by going once or twice a week, slowly fading it to 3 classes per week plus increasing the gym to around 2/3 hours per week, so about 5/6 hours per week, my diet however is terrible, I do not know what I should be eating, can anyone give me any tips as they would be much appreciated, also is this too much, enough, or not enough training per week. Many thanks to any replies.