Scroll down to Accent color and pick a shade you like.
💡 If the toggle is greyed out, make sure you have selected "Dark" under the "Choose your mode" setting at the top of the page. Windows 11 does not allow accent colors on the taskbar while in Light mode. change color of taskbar windows 11
Set "Choose your default Windows mode" to Dark . (Note: The taskbar color toggle will remain greyed out if this is set to Light). Scroll down to Accent color and pick a shade you like