How long till your baby learned how to suck the bottle to eat?

Julii
My baby Jason was born at 34 weeks 2 days because of vasa previa. He came out healthy but has fluid in his lungs so the doctor put something down his mouth to take out the fluid.. That lasted two days and then he was diagnosed with jaundice and was out in an encubator and under a light for about two days. That's why he is now looking a little red/orange .. Now he is good!!! However with all treatment for the fluid in his lungs he was not able to eat properly.. Now he doesn't know how.: he doesn't show much interest for eating. I try and breastfeed but he doesn't really care for it.. The nurses have tried bottle feeding.. At first he wasn't interested.. Yesterday he took about 10cc from the bottle in the morning and 29cc for lunch but 10 cc in the afternoon and last night he showed no interest for the bottle again! My question is how long did it take your little one to learn !!!