Cold and Flu are both respiratory tract infections caused by different viruses. They have both very similar symptoms but the symptoms of the flu are in general worse than the common cold. Most people with a cold experience a runny or stuffy nose, sore throat, cough, watery eyes, congestion, headache, and sometimes a low-grade fever. The cold and symptoms develop often slowly. The symptoms of flu are similar but develop suddenly and more serious, fever is common.
Both illnesses can't be treated with antibiotics because they are caused by a virus.
In the case of the flu or if you belong to a risk group it's always better to see a physician and decide then which treatment is the best. There is no medication that cures the flu or cold but natural medicines can help to lessen the severity and shorten the duration of the symptoms in many people.