I search things up and apparently professor binns was in hogwarts legacy and there's a side quest with him???

Is this a mod or something? I'm almost finished with the game (i'm about to start the part where you make a wand to access the repository) and i have never played that part. when and how and where can i play it?

Thanks guys and have a greeeaaat day!!

Ps accio @Stormshock the animus ElectricWing !