Step 4: Sweat
Shove the pipe into the coupler and sweat it with your solder. Other instructions will let you know, but I will repeat, you don't melt solder with the flame, you melt solder by heating up the joint until it is hot enough to melt the solder by touching it with it. If you try and heat the solder with the flame and just sort of paint it on you will become extremely frustrated with how badly this is going for you and very likely light yourself on fire to bring an end to madness.
Yes my soldering is ugly, cut me some slack. It was raining and dark, I was drunk and had a huge knot swelling up on my head and I'm no plumber. The solder held so I'm happy. Tomorrow I guess I'm cleaning up this hole in the wall.
Let the pipe fully cool off, to the touch, before kicking the water back on. Don't try and splash any water or anything on it to speed up the process, this might shock your whole mess and result in another leak. Once it's cooled off put pressure back in the pipe by turning on the water main, and open your hose valve and bread bits may or may not shoot out. If you have a little filter in there you can take that out and speed up the process, but the bottom line is the junk trapped in the pipe is bread and will pretty quickly disintegrate and get out of your system.