When cookie recipe calls for cake flour and you have bread flour how can you fix it?

Bread flour contains a higher percentage of gluten than cake flour. Gluten makes bread dough elastic and forms the structure of bread. Cake flour has less gluten so that the cake "crumb" is tender, not bread-like.

Depending entirely on the type of cookie you are making, you might get an acceptable result with bread flour, but the texture of the cookies might be tough or chewy rather than tender and crumbly.