In an 1988 Acura Legend why when you turn the headlights on rear lights are off and vice versa if also come braking?

This is not accurate, the rear lights should be on whenever the headlights are on and the brake lights should come on when the brake pedal is pressed, regardless of whether the headlights are on or off. If this is not the case, there may be an issue with the electrical system of the vehicle and it is recommended to have it inspected by a qualified mechanic.