Upon troubleshooting the central humidifier, I realized that it isn't connected to a water supply line (new property woes). One end of the flexible copper pipe is connected to the humidifier and the other end has what I've learned is a saddle valve (encircled in blue) and needs to go.
A plumber that installed a softener earlier probably left this white pipe (encircled in red) in case I needed to add something later. I'm guessing this is where I can tap into for supplying water to the humidifier?
I also noted a sealed-off copper pipe (encircled in green) which I could/should use since that's the 'softened' water and may be healthier for the humidifier filter.
I do not know how to solder and don't mind learning but I have basic DIY experience with push and compression fittings. The tools I have include a copper pipe cutter, deburring kit, DIY tools and the desire to buy more.
Which type of pipe do I need and how do I go about connecting everything end to end? Thanks.