For example, if you see the figure, you will find that now, if it's white's turn, he can move from 6 to 3. And then whatever the black player may do, the next move that white will play will be moving the marker from 5 to 2 and he will win the game (three in a row).
Now, you have to acknowledge everything and decide that if both the players are playing with the perfect strategy, will the white player (the first to play) be the winner always? Or the black can win? Or they can lead the game to a draw every time?