QuickBooks Online comes with tons of helpful reports you can refer to for your business. Assessing your business health is an important step in your success. Showing tax information in your reports may be helpful, depending on which report you're looking at. I'd be happy to explain further.
The steps regarding showing tax on a report may be different depending on which report you're looking at. Some reports allow you to show tax info, and some reports don't.
The best way to see whether or not you're able to include tax information on your report is to click the small Gear icon at the top right-hand side of the report itself. If you expand your options here, you may see sections pertaining to taxes, which you can check-off to include. All of your report customization options are located here, or through the Customize button.