The ceiling light is broken, buy one that won t wiring!

If you do not connect the sectional switch, you can connect the black wire together to the neutral wire, and the white wire to connect the live wire of the switch. >>>More

If you want both lights to turn on at the same time, connect the two wires of the other light with the headlight wire. If you want to control them separately, buy a two-way output breaking controller, which can be controlled with the original light switch. It can be lit by each lamp alone, or by both lights at the same time.

Yes, the middle is the live wire, or it is written L, or it is a different letter except L1 and L2, I don't know what you are writing, it is best to have a picture, two use the wire to bridge the other two ends of the live wire, and take a section at the other two ends to connect the lamp separately.

One is fixed on the roof with screws, which is relatively simple when dismantling, as long as the ceiling lamp is removed stably when the screws are removed. >>>More

Your set screw should be behind the back, reach out and touch it from the back to see.