What Is YouTube Watch Later? ~~~ home --- Library ---- drill down a bit ~~~ watcher later ---- actually it is inside the top upper left --- click on the three-lines

 What Is YouTube Watch Later? ~~~ home --- Library ---- drill down a bit ~~~ watcher later

 actually it is inside the top upper left --- click on the three-lines next to the Youtube logo

a menu will pop out  , you will see watch later