The water contained in a baobab tree is drinkable for humans and if you can access the water in the baobab tree you can drink the water from a baobab tree.
Some people do use the water from a baobab tree to drink when they don't have access to other drinking water sources.
The water in a baobab tree is much cleaner and safer to drink than water in most creeks and streams but if you can find water more easily it would be better to drink water from those sources as long as they are safe.
It can be hard to get the water out of a baobab tree unless you know exactly what you're doing because the water in a baobab tree is not easily accessible for you to drink.
The baobab tree is storing at least 79 percent of water inside it so you can get lots of water from the baobab tree.