How do you find out if your 1776 continental currency coin is real?

The easiest way when dealing with early American coinage is to take it to a coin dealer.

These coins are hard to evaluate until you hold them in your hand. Since many of these coins were abused, buried or otherwise damaged and since the production methods were primitive by today's standards, its really hard to describe what makes a coin genuine or not.

The first thing I'd do though is search for any indication that "COPY" or "REPLICA" (or sometimes "R" or "C" ) is stamped on the coin, if you have one of these on your coin, you can know for sure it is a fake.