Greetings,,,
Grab some item that you're throwing away, or that someone else trashed. Radio, computer, etc. Anything with a circuit board. Heat up a few component connections and pull the leads out with pliers. Put them back in. Repeat until satisfied that you can heat a solder joint. Any damage is no problem. Cut an AC cord off something. Remove insulation an inch. Solder that heavier item. You can now add ac cords to your units. Proceed at your own rate from there.
Warning. May be addictive. Not for small children, hamsters, or mice. Your mileage may vary. Not valid in all states.
Keith