Struggling with OCD and Contamination

I struggle with people touching my food BADLY. I can not stand it when I am in view of people cooking, and people touch the food without washing their hands first. I have to make all the food myself (when I am alone) as that feels better as I wash my hands frequently when cooking. If they touch my food, my OCD gets triggered. I also struggle with OCD when I'm at school. I have a literal FEAR of germs and contamination to the point where I sanitize everything and change my outfit as soon as I get home. It triggers my OCD if I do not sanitize or wash something and I flip out. I still wear my mask while in public, but switched to the disposable ones. How should I manage both of these so that my OCD decreases in intensity?