Alright my 6 mths lo is very depended on feeding to sleep (naps and bedtime) He sleeps through out…

Alright my 6 mths lo is very depended on feeding to sleep (naps and bedtime) He sleeps through out the night and will nap for sure 2× a day (sometimes he'll throw a 3rd in there) we feed on demand for the most part but he is very consistent 6oz every 2-3 hours. How can I break the dependency of a feeding for sleep? Where can i find info? What can i ask his dr next week to help? TIA.