When you select a product in your generator section, in the opened page, you can see a View button right next to Publish.
After publishing the description you've chosen, by clicking on this button, you will be redirected to your Shopify product page.
There, you are provided with a set of tools that will allow you to style the description: e.g. you can change the font style to italic, bold, etc. You can change the font size, color, and alignment. You can also add links, tables, or pictures if you want.