I purchased a mac. How do i get the the 3 free months of apple tv

For Macs, users have to additionally sign in to the TV app (menu Account), for the redeem option to appear.

Read here how to redeem: Apple TV+ offer - Apple

Read here about the conditions: Apple TV+ offer - Terms and conditions - Apple

Read here if you have trouble redeeming: If you can't redeem your promotion for an Apple subscription - Apple Support

Good evening,

Congratulations on your new MacBook Air, and welcome to the Mac family. You're able to take advantage of this offer by completing the following steps, and I'll walk you through those now.

1. Open the "TV" application (by default, this should already be in your Dock, if not, use the key command ⌘ + SPACE to open Spotlight Search, then enter "TV").
2. Navigate to the "TV+" section of the TV application.
3. You'll see an offer for three months of Apple TV+; you now have the option to accept or decline the offer.