Please don't get babies that young. They are near impossible to bottle feed and the mortality rate is so, so high. They can get a million illnesses that young, not to mention diarrhea from the formula which is fatal in rabbits. Get one a bit older. Just because the babies are cute, doesn't mean...
Pine shavings are not safe for rabbits. They contain an acid that causes upper respiratory. You can use Aspen in place of it though. Here is a link you can read.
https://www.tinytoesratrescue.org/cedar-and-pine-toxicity