These are separate verbs. One can try to deduct the meaning from the built-in preposition but there are transferred meanings involved which don't seem reasonable at first glance. Or maybe not even anytime later.
bauen (to build)
anbauen (to attach something (by building); to grow fruits and vegetables)
The preposition an means tight to, so attaching something is straight forward. But why grow fruits and vegetables? NO ONE KNOWS.
ausbauen (to add interior; to intensify; to refine)
The preposition aus means out of. Why is adding interior, intensify or refine out of? NO ONE KNOWS.
Uh, and by the way, wine is also being angebaut. That means to grow the vines. While ausbauen means to refine the product by putting it in storage for months to years before selling.
And of course, a whole range of prepositions and other prefixes can be combined with bauen, too:
einbauen (to build something into something else)
abbauen (to remove something previously attached)
umbauen (to rebuild something)
überbauen (to build something on top of an older structure in the ground)
zubauen (to close the last gaps by building)
erbauen (to construct)
verbauen (to build too much stuff into a compartment)
vorbauen (to prepare oneself)
Treat them all as separate verbs. And for all the other verbs, too.