Basic wiring is intimidating for sure. But think of each jobber as a battery. A key switch is a jobber. A coil is a jobber. A stator is a jobber.
Keep thinking the jobber is like a battery. We have to hook a (-) up to ground and the other jobber's wire to (+) is to make the light turn on, the coil goes hot we turn the key on.
No matter how I explain it, was there a wire in and wire out of a light bulb? Yes. When there is a toggle switch is just call it a key, is that jobber just having a wire in and wire out it goes off and on is the hot to ground? Yes. Is not the coil one type of jobber that there is only one wire in and one wire out is how you hook up a coil, sans you know the two plug wires coming out of that coil goes to the plugs. But the idea is that jobber is WIRE IN and WIRE OUT is the JOBBER.
The next puzzle to look for is who is hot and whom be cold? Usually, green is grass for ground meaning. Black is ground if you dig deep enough, things go black. So you are looking for your (-) wires to see if they have integrity or are snug to the frame or a [ground] junction on the bike somewhere?
The other side of that color scheme is think about how white might represent how hot (+) that wire could represent, as would red is the wire that is hot to the touch. Here are your jobber wires that have to be hot from the battery via the key switch. You are going to need a tool to know who is hot and who is not?
You want a pointer style so you can stab into the wire covering. This also can back probe right at the connectors as they are hooked up. This way you can tell who is hot on the one connector side, then you probe the other side that should turn hot too and oops, no lighty.
You now can see if the other side of the connection is:
1. Corroded so as to stop connections continuing.
2. Male to female wires are secure but not touching internally between prongs.
3. A wire was pulled out or hanging outside the other side of the connector and oh look Moe, no need for the test light probe. So the question is...
... What was the last thing you did to the bike? I usually turn the key off after a ride and it sits. How could it not have spark if say the gas is so stale from sitting, and so is the crap in the carb, or say the injector is varnishitstuck?
a. My bike may turn over, have gas and spark, but sure as shit is I'm going to eliminate what the compression reading is so I do not chase my tail.
b. Do I have spark is the next move? I want to see if spark is present. I have a spare/new plug around, which is to say, I shove it up the plug cap and ground the plug to the head. I tap the starter so I hear at least it crank over twice is once is enough you see spark or not?
c. I have both spark and compression is one amigo left. If my bike sits, my gas decomposes into a green varnish after awhile. It will clog any fuel from leaving the carb. I may not have a spark or a compression problem but a fuel problem.
We see the 3-wire walk as well as the 3-amigo walk? Make it fun. Frustration is fun or it wouldn't be fun, right?