The Building a Library quest in Arc Raiders is fairly simple, especially as it's confined to one specific building in the Buried City. Speranza's resident explosives peddler, Apollo, asks you to find three books in the city library, namely a detective, romance, and adventure book. The genres don't matter much; you just have to find three specific stands inside the building.
With a metro station right outside (provided it's still open), I'd recommend using a free loadout for this one. Otherwise, here's where to find those three books for the Building a Library quest.
