It's ideal to give BM till 6 months and in case needed you can give earlier too. But choose a formula milk that atleast helps in overall health development and also improves gut health. I have heard prebiotics are useful.

Breastmilk is good for baby but your baby demands more milk and your milk is nat sufficient then start formula. After one year you can start cow milk.

Whole cow milk can be introduced after 1 year of age

Only after 1 year do they suggest introducing whole cow's milk.

Generally speaking, you should transition your baby off formula around 12 months of age. But there are exceptions: If your baby has special dietary needs, a milk allergy, or developmental delays, your pediatrician may ask that you continue giving them some formula.