The Windows 10 Taskbar already enables you to pin your favorite websites, but navigating to a specific one is a guessing game with Cortana. If you wish to skip the frustration, there's a simple tweak that allows you to add your own URL field, thus giving you the ability to navigate to any website without needing to open a browser first.
1. Right click the Taskbar and unlock it by clicking the Lock the taskbar option. If this option isn't checked, you can skip this step. It should come checked automatically, though.
2. Right click once again and click on Toolbars > Address.
3. Now, you have a URL field in the bottom right of your Taskbar. For doing things, simply key in a URL and press enter. Windows will open the link inside your default browser.
4. To eliminate it, simply work in reverse order and repeat steps 2 and 1.