Peter here from Shopify Support.
If you're setting up manual rates, then it would require that you create a rate for each possibility as manual rates can't automatically duplicate based on the items in the cart. Alternatively, you could also look into using third party carrier calculated rates as this will automatically display a shipping rate based on the customers shipping address, and products they've added to their cart.
If there's anything else I can help with please don't hesitate to reply back and I'll happily help out!
All the best,