How do you get a replacement apple card if you don't have a iphone or ipad?

If it is a replacement and not a new card all together then you would call Goldman Sachs to request a (replacement card) if you activated a Physical Apple card the first time around and this is your second one you should be good to go because you were already in the system that is why you can also pay your Apple card through the website as well and not just in your wallet through an iPhone

You cannot get a card if you do not have an iPhone.

you cannot activate a physical card without an iPhone. Even if it is a replacement card. Each physical card has a different card number.