I have an enlarged lymph node on the right side of my groin. I've had it for 6 years and it's the size of an almond. Cancer? Causes?

Old infection. The node got scarred due to an infection in the lower limb, probably when you were younger. As it has not changed in 6 years, it is not a cause for concern for cancer or anything else. Leave it alone. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.