It doesn't. Fairer skin would reflect more radiation, than darker skin, but it gets burned in the process.

I don't think skin color has much of an impact when withstand heat, as sweat is a much stronger temperature regulator. If it's humid heat, it becomes a matter of circulatory efficiency, body mass and plain endurance, as sweat can't evaporate and actually makes it worse.

Source: grew up in tropical coastal region.

It does if you spend time in the sun.