Baby’s vitamins and food

Anyone here with a 6-month-old breastfed baby? Have u started giving water and solid food to your lo? How much water do you give your baby a day? Also am wondering if your baby’s pedia has the same advice to you with regard to baby’s vitamins. My baby’s current weight is 8.7 kgs. his pediatrician advised me to up his vitamin intake. From .5ml, she said i needed to start giving my son 1 mL of Ceelin drops and 1 mL of Nutrillin because he’s a big haby.