How to encourage 14 month old to drink water?

My son has had issues with food for a long time, he’s just now finally getting on a good schedule and the pediatrician is very pleased with his progress but I can’t seem to get him to drink more than a small sip of water and he throws a fit.

How can I encourage him to drink more water instead of milk every 3-4 hours throughout the day.

I still give him milk with meals and before brushing his teeth at night. But water is a struggle.