Whether baby is feeding adequately or not can be estimated by his urine output. If he passing urine atleast 8-10 times in 24 hrs then ur child is feeding enough.
If ur child is refusing breastfeeding that could be because of bottle feeding. As it is easier.
Next Steps
Try feeding on demand. As much as the baby wants or atleast 2 hourly.
Health Tips
if ur child is really not feeding well, not looking well, not passing frequent urine. then u must visit a pediatrician .