S.H.
Always nurse on-demand.
Always nurse first, BEFORE solids. Otherwise, baby will be too full to nurse, and then, they will wean from breast. And if giving solids before nursing, your milk supply, will drop.
For the 1st year of life, breastmilk or Formula, is a baby's PRIMARY source of nutrition and calories and intake. NOT solids and NOT other liquids.
Nurse on-demand, 24/7, day AND night.
At growth-spurts, they will need more intake and nurse more and more often. Your milk production, is supposed to keep up, with baby.
9 months old will be a growth-spurt time. And every 3 months after that.
When/if a baby is teething, they will also sometimes nurse less.
As they get older, they also nurse more efficiently.
For my kids, even if they were on solids, they really nursed a lot still, on-demand, every 3 hours at least. They had ginormous appetites. My milk was ample.