The 1943 Penny is a steel wartime cent (penny). You can read a detailed description on Wikipedia. The 1943-D penny had 217 thousand minted, while 1944 and 1945, back to the traditional copper design, each had well over a billion minted.
The value of a 1943 Steel cent is listed on the cointrackers website.
You can post it on eBay, or take it to your local coin shop.
This site is for dealers registered with the American Numismatic Association: