There are many possible reasons for fluid retention, but given your presumed poor intake for two years, you may be suffering from severe protein/calories malnutrition. Normally, protein in the bloodstream keeps plasma fluids inside the blood vessels by way of osmosis, but if blood protein levels go down, then plasma fluids leak out into the tissues to cause swelling.  Malnutrition, regardless of cause, can lead to serious disruption of the cardiovascular and renal systems.  Please see your doctor without delay for an accurate diagnosis and treatment plan.  When you say, "I want to get rid of it and don't know how," the answer is to eat a balanced diet and, for that, you will need help.