I recently started Death Stranding, I am at chapter two. I seem to have a faint memory of reading that there is a way to head out without BB? (it was about getting around the map and BTs without the help of BB I think, strangely now I can't seem to find anything about it, only a video where BB is not present on youtube) As far as I have progressed in the game, it seems to not be an option not to take BB with me. I know it is somewhat tied to the story, but will there be an option later in the game to leave BB in the private room or does Sam carry it with him all the time?
There is no option to head out without BB. Whether you can head out with or without BB is dictated by the story.
BB will become unavailable as soon as Episode 6 begins, and will return at some point during Episode 7 (which is a short and linear episode).
At best, you can influence when to take BB with you or not, by delaying the end of Episode 5, and rushing through Episode 6 (and 7).
For the record: Episode 6 begins as soon as you enter your Private Quarter after connecting
Mountain Knot City
to the network.