With 300 marks out of 600 in the KEAM Engineering exam and an Ex-Serviceman special reservation, your general rank may fall between 10,000 to 20,000, depending on overall performance trends. However, your special reservation will improve your chances significantly during seat allotment. You may get admission in good government or aided engineering colleges in Kerala, especially in less competitive branches. Keep checking the KEAM official rank list and counseling updates for your exact position and college options.