Help identifying cable/jack

All that is perfectly correct assuming you have a large deskside PC, or a Mac. If you have a PC Laptop, chances are you can’t do this at all. PC laptops mostly have very sensitive mono microphone connections and no provision for musical instruments or stereo. If you look closely at your machine, does it have a little microphone symbol next to the audio connections? Or does it say Mic-In?

You can add an external USB sound card and you may not have to buy as many adapters. Many musical performers do this.