If you have a non-physical product, you'll want to make sure you have the box unchecked on Shopify that says "This is a Physical Product".
On Shopify Admin Dashboard, go to Products
Click on the specific product
Uncheck the box that says "This is a Physical Product".
By default, Shopify will have this box checked with new products, so you just need to uncheck it.
Customers won't have to enter their shipping address or choose a shipping method when buying this product.
This is the ideal setup for memberships, services, or digital content.