Please help me out, I cannot get the brush back that can add/remove background

[dust92]

Guys, thanks so much! So for some reason I thought you could repeat steps of the Foreground Selection at any time, but apparently when done, you can't go back.
The examples are EXACTLY what I needed and also the other comments helped me out a lot, thanks so much for your quick and complete replies, we all have busy lives, so you taking the time to respond is greatly appreciated!