Tartaruga do Esgoto de Dalaran

I had to complete the intro quests for the campaign, and once I was sent to find Adelgonn at Freywold Village, the turtle showed up there.

Dalaran Sewer Turtle is located at Feywold village up on the hill on the south side, he will be next to a Dalaran Sewer Rat, upon speaking to him he will ask you for 5 Dornish Pike, after a few minutes, his dialogue will change and next he will want Fish and Chips, the dialogue will change to <The turtle nudges the fish and chirps happily. This will help a lot. He just needs time.>

After a few more minutes, you can then interact with the turtle again and give him Goldengill Trout the dialogue will then change again to
<The turtle is stunned at the size of the fish. He comes to his senses and stamps his feet in appreciation.

It will take time to find the rest of the family!>

You will find that the turtle has gone back to his family back in the main city located at Stoneshaper's Atrium, it'll be marked on your map but he is by a tree with the Dalaran Sewer Rat in a tree.

Interacting with the Dalaran Sewer Turtle will give you <The turtle sways his head to try and get your attention. He paws the ground.>

Upon interacting, and leaning in closer, you'll be able to loot him as a companion pet via Sewer Turtle Whistle