When I have a cold I try to do a short exercise activity that's not too vigorous like walking, slow jogging, elliptical, or some sort of 20-30 min medium cardio. As far as food goes try to make sure you're eating a little bit of fruit and veggies but also my fav sick foods are oatmeal/porridge, light soup/miso/chicken broth, crackers, light things
get well soon!