I'm self conscious about my body

I'm currently dating this guy and things are going good so far. We have talked about having sex and I'm down for it. But I'm honestly really anxious. I'm 18 and a virgin and I don't like my body. I currently weight 327lbs. I'm embarrassed about my weight and am trying to improve myself. I'm just scared that he'll be disgusted by my body. I have dark patches and really ugly inner thighs. I'm extremely embarrassed and I don't want it to ruin the moment. Are there any tips on how to felt less self conscious and how to not let my fear ruin a good moment?