Shew is not a different word. It is only an old way of spelling show. For a long time English writers used shew in books, letters, and the Bible; you will still meet it in Shakespeare and in church language from centuries ago. It carried all the usual meanings of show: to let someone see something, to point something out, or (as a noun) a play or display. People said it the same way they say show; only the letters on the page were different. By the 1800s the spelling show had mostly won, and shew slowly dropped out of everyday writing. Nobody uses shew now except when they are copying old text on purpose, or trying to sound antique. If you find it, read it as show and keep going.