Sir it's Marginal Chalazion.
Follow few instructions:
(1) Hot compress to both eyes 2 times a day for 15 days ( Can dip clean cotton in warm drinking water and keep over closed eyes for 30 seconds)
(2) Avoid rubbing of eye
(3) It's good to maintain Eye hygiene with baby shampoo 2 times a day (Take on tip of your index finger any baby shampoo say Johnson baby shampoo or Himalaya baby shampoo , wet your eyes and gently rub the shampoo with your finger on closed eyes for 15 seconds and thoroughly wash off with drinking water)
Next Steps
Looking at the duration of the issue better to go for definitive treatment of Chalazion Incision and Curettage.