Thanks for your query.
It is normal for breastfed babies to pass 5 to 6 motions a day,color ranges from yellow to green
is normal,as your child is also doing well so nothing to worry.
Since your baby is 6 months of age i suggest you to start complemantary feeding that is in addition to milk give him rice water,dal water,coconut water.
Start with one food item and give it for 4 to 5 days before introducing other.
Wishing your baby good health.