product key

I want to share my experience for those who have lost their Windows Product Key. I built 2 pc's over the last few years & the labels I attached to each Windows Product Key to designate which pc it went to came off during a move, anyone in this position knows its not easily retrieved, except for...

I've lost my Windows 10 Product Key during a move & need to retrieve it from the pc I built. I've tried searching YT & google without much success, most information is on how to locate on store bought pc's. Anyone with a step by step or a link would be helpful . TIA-Jp