23F. Strong family history of colon cancer. Syncope, h/h 7.4/27.7. Fe studies showed anemia, hematologist referred to GI. Chances of cancer?

Low. What is the earliest age which you family members had colon cancer? If you are ten or more years younger than the lowest age of the cancer patient, your risk is very low. Your anemia is more likely due to blood loss in menstrual bleeding. You are doing the right thing by seeking care. Follow your doctors' instructions.