When should i give him cereal?

Amanda
My pediatrician had us schedule his next check up at 5 months skipping or 4 month appointment... But I heard you are suppose to start giving them cereal at 4 months... I'm clueless on anything because I'm a ftm. How do I know if it's time and how often/much to give him...? Wish the dr didn't leave us in the dark like this.... I don't want my baby chocking due to not being ready....