adding more than one option for shipping

hey folks,

im trying to read through this https://docs.woocommerce.com/document/setting-up-shipping-zones/

but nothing im applying is working. I just want there to be two options for shipping for every items in the store. 15 Dollars for an Xpress post enevelope and 25 if its to be rolled and tubed and shipping but it won’t let me add more than one “flat tax” per zone? what is the best method for this?

thanks