Using tabbed browsing, you can open multiple sites in a single Internet Explorer 11 window, each of which you can close with the "X" icon, your mouse wheel or a keystroke combination. If the tab reappears after restarting the browser or clicking the Home button, the URL in the tab is configured as a home page. To permanently remove that tab, reconfigure your home pages in Internet Options.
Closing Individual Tabs
Click the small "X" to the right of the tab you wish to close. Alternatively, click the tab with your mouse wheel or press "Ctrl-F4" or "Ctrl-W." If you kept IE11's default settings that warn you about closing multiple tabs, you can also click the larger, upper right "X" button to close your browser; when the warning appears, click "Close Current Tab" to close only that one tab. At least one tab always remains open, so to close your last tab, you must close your browser.
Removing Home Page Tabs
Click the "Settings" gear icon and then select "Internet Options." In the General tab's Home Page box, click and drag your mouse to highlight the entire line that lists the URL of the tab you want to remove. Press "Delete" and then click "Apply." Doing so won't close the currently opened tab, but it prevents it from reappearing each time you open your browser or click the Home button.