Help! 12 month old.

My son does eat breakfast, snack, lunch, and dinner but he’s not interested in eating everything. He gets his 16 oz of whole milk today since I finished up his formula last night. I have no clue how I’m going to wean him off the bottle during the night because he always wakes up for a bottle. I can try water but i doubt we would drink it and prefer not to give milk because of cavities. I mean if he would eat better, it wouldn’t be an issue. Any suggestions would help!!!