How do I get my 3 free months of Apple TV for buying a MAC Book Pro

but have been too busy to sign up

If you are eligible, then you have to redeem the offer within the first 90 days after first activation of your new qualifying Apple device. You should also do the redeeming on that new qualifying Apple device, in the TV app. Find the “Enjoy 3 Months Free” redeem button there. For Macs, remember to additionally sign in the to the TV app (menu Account), with your Apple ID, else the redeem button will not show.

Hi Beingthere,

You can find information on starting your trial here: Watch Apple TV+ on your favorite devices

Keep in mind that if you've had a free trial before you won't be able to sign up for an additional trial. We hope this helps.

Take care.