I have a small circular scab on side of my foot for a while, i picked it off &theres a chunk missing with red dot present. could it be skin cancer?

Need more info: It is unlikely to be skin cancer. Did you hurt that site? Was it subject to constant rubbing from shoes or something else? For now watchful waiting is appropriate. If the lesion does not bleed, ulcerate, become foul smelling or has a discharge, you may give it time to heal. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex. Get HPV vaccine.