There are 24 checkers pieces in a game of checkers.
You'll just have to use some other kind of marker.
English Draughts, aka American checkers, is a board game that is played on an 8x8 board consisting of interchanging colors. For a complete explanation, just go to the link below.
Sure.
At the beginning of the game, there are 40 spaces that don't have checkers on them.