This is general information gathered from widely published parenting guidance, not medical advice, and it will not match every baby. Always put your baby on their back to sleep, in their own cot or Moses basket in the room with you for the first six months, with nothing loose in the cot. Follow your health visitor or GP over anything here — they know your baby and you do not need to justify disagreeing with a website.
In the UK the NHS Birth to Five app and the Start for Life site cover feeding and sleep, and you can call 111 any time if you are worried. If you are struggling, saying so to your health visitor is not a failure. Newborn feeding amounts here follow the usual NHS guidance of roughly 150 ml per kg per day, which varies a great deal between babies.