A little before 4 months. It all depends on the baby I think! My son is pretty advanced on growth and things and was giving the signs (reaching for food we had, watching us while we ate etc.) the doctor okayed it and he does well.
I gave my daughter at 6 months but some some start at 4 @leeeeromero
my son was 6 months when I introduced him to baby food an cereal
I waited until my son was 6 months, but I also did baby led weaning 😊