Which mouthguard would you all recommend plus other equipment?

I just started training in boxing, kickboxing, and Mixed Martial Arts. Which mouthguard would you all recommend. My mouth is not the straigtest so I would have to mold my own right? What kind of cup would you recommend as well? And what kind of Shind guards would you recommend? Also what is a Rashguard? Is it worth it? They look like tight shirts?