When you create a new product in WordPress, you can set the price using the Add New Product page. The default price is set to $0.
However, you can change the price to anything you like by typing in the new price in the text field and clicking the Update Prices button.
If you have an existing product, you can change the price using the Settings page. To get to the Settings page, click the Settings tab on the Admin area of your WordPress site, and then click the Product tab.
In the Product Settings section, click the Price link. You can then change the price to anything you like.