Amateur here seeking advice. I've found some resources on Utube, also read about national electrical code and that you can't run a switch/power source from a power box that is used for major appliances, i.e. dryer, if I'm understanding that correctly. I have questions about my power source, forgive my ignorance, this is all greek to me.

Know the basics of a three way switch and the wiring involved with switches and outlets, we actually have an existing three way switch. Basically, we'll be installing canned lights in a non insulated basement ceiling. The existing lights are fluorescent, some are hard wired, some are plugged directly into outlets that are in the ceiling, so existing electrical wire isn't installed, meaning the 14-2 and 14-3 I just picked up from the hardware store. In the ceiling is just the metal conduit, outlets and junction boxes. In other words, if the 14-2 wire was already connected to a power source, I'd be able to hook up the canned lights. I'm stuck.

I have a diagram on how to wire lights in a parallel, but unsure about my power source, DUH. Can I just run power from the "junction" boxes on the ceiling, or the outlet boxes? When I say junction box, there are metal conduits running to these boxes, and the boxes are capped off with a cover. How do I do this?

Second, we'd like to add a single pole switch since the three-way switch operates two separate living areas, but not sure how to add a switch, or again, the power source. Does code require that the wire be run through metal conduits or can I just run it through/along the ceiling beams like I'm seeing everywhere on the internet?