Can I add a page that links to an external website when clicked in the menu?

Can I add a page that links to an external website when clicked in the menu?

Yes, you can. 
  1. Go to Configuration -> Menu.
  2. Click Add Menu Item in the top-right corner.
  3. Click External Link in the menu on the left.
  4. Enter a menu name and the URL of the external page.
  5. Click Save. Your page will be linked to the external website. 
Note: Click the Target switch to open the page in a new tab.