Hm. I've seen a good deal of amps where you just bridge it by the way the speaker is hooked up to the amp, nothing to do with a switch/button. But I haven't bridged much, and when i have, it has been my older PPI amps.
No. To bridge an amplifier, one channel has to have an inverted output. What this kid has, is an ancient Kraco amplifier that was built in the 80s or early 90s, and sold for about $40 at auto parts stores and K-marts. It's a piece of trash best used as a door stop. It never supported bridged mode, and never will.
He'd be better off spending $50 on a better used amplifier from craigs list.