Has anyone swapped from breastfeeding to bottle?

My little one is a month today and only just back to birth weight but that’s due to loosing a massive load of weight when born and other complications.

I just feel I’m failing him. Everyone I’ve seen tells me different things about how I’m breastfeeding , some it’s good and some reposition him and I’m struggling with the new position I was given on my right side only and it’s mentally getting me very emotional

Has anyone got any advice?