If I buy an Apple Watch online at target or Best Buy, can I get apple care plus in store after I receive it? Or do I have to buy the watch in store to be eligible for Apple care plus?

I Would like to buy an Apple Watch but I want Apple care plus too. I would like to order online from target as the store near me does not have the watch I specifically want. If I get the watch online, can I take it to the store after I receive it to purchase Apple care plus for it or will I have to purchase them both in store to be eligible for Apple care plus?