To do this kind of thing requires you to master some fundamental PS functionality - actually the fundamental operations of digital image manipulation.
Broadly, you need to select just the area to be affected [your bro] and apply appropriate effects [increase brightness].
How exactly would I do it? Depends a bit upon the image. I would possibly select him using the extract tool [having copied the layer] and tidy up using the history brush and/or QuickMask. I'd insert a brightness/contrast adjustment layer, with a mask made from this selection. I'd add a gradient to this mask.
Hopefully this will lead you in the right direction Brad and guide you to the right things to look up in the manual and online help. If you need more assistance, do come back.