Hey Terry,
There’s a couple of settings to get this going.
Under WP Admin ? WooCommerce ? Settings ? General, you want to check the box next to Enable Taxes, and click Save Changes. That reveals your Tax tab.
Select that tab and choose the option next to Prices entered with tax, which can either be Yes, I will enter prices inclusive of tax, or No, I will enter prices exclusive of tax.
If you select yes, your shop will take your existing product prices, and seperate the tax out from it. If you select no, it will take existing product prices, and add tax to it.
Either way, at the bottom of that page you’ll see Price display suffix, where you can add incl. VAT, or ex. VAT, as examples, which will display regardless of yes or no.
Here’s a doc with more detail and context:
https://docs.woocommerce.com/document/setting-up-taxes-in-woocommerce/