The owlbear cub in Baldur's Gate 3 can be found initially in the Owlbear Nest, a cave located northeast of the Blighted Village and near the Druid Grove. The entrance to this cave is just north of the bridge west of Silvanus Grove and east of the Blighted Village. Inside the cave, you will encounter the owlbear mother and her cub

. After the initial encounter, regardless of whether the mother survives or is killed, the cub will later appear at the Goblin Camp, which is west of the Druid Grove and Blighted Village. At the Goblin Camp, the cub is found near the entrance, surrounded by goblins, and is involved in a mini-game called "Chicken-Chasing" run by a goblin named Krolla. You can interact with Krolla to negotiate the cub's freedom and eventually recruit the cub to follow you back to your camp

. Once recruited, the owlbear cub will appear at your campsite after a few days, where you can feed it and it will become a pet that can be summoned and interacted with throughout the game

. In summary:

• Find the owlbear cub in the Owlbear Nest cave northeast of the Blighted Village.
• Later, find the cub at the Goblin Camp near the entrance, surrounded by goblins.
• Negotiate with Krolla to take the cub.
• The cub will then appear at your camp as a follower and pet