It is not that you don't know how to deal with people. It is the thought what they think about you. You have to understand yourself first, judge between right and wrong, be assertive and deal with people. This will be a perennial issue as throughout your life you will have to deal with people around you. We are social animals, hence cannot run away from the facts.
Next Steps
A Counsellor can help you channelise your thoughts. Take appointment and consult one in your city.