Hello @lil_sprout and thanks for your question. You can set up shipping options here:
Online > Fullfilment > Shipping.
You can set up flat rates or real time shipping rates. Find out more info here.
You'll have to define some kind of shipping for your online orders, so when you customers place an order the website knows how much to add for their shipping. The integration with Shippo allows the mailing info to auto populate in the Shippo website so all you need to do is print the shipping label. You'll pay the shipping cost to Shippo for the label in your billing with Shippo, but the customer will have paid for their shipping through Square when they order on your website.
To set up real time shipping (where the rates are based on the carriers) check out this article here. Note, you'll need to configure at least one shipping box dimension as well as enter item weights for calculation. You can find out the details in the link above.
I hope this helps answer your question.
