in section 3:40 in video they use the line tool as a guide how do i do the same in adobe animate 2020.
Your link is to a Google search for "share quick time movie url". Thanks, I needed a laugh today.
As for your (probable) question, this is basic functionality that is already explained many, many times on the internet.
The line tool in my video for example is used as a guide to correct the lower arm movement of a character. On the top layer frame is the line tool and on the bottom layer frame is the character and as the artist draws the line on "one frame" the line tool is one drawing and appears the artist is drawing different lines on character arm to use as a guide to fix the arm movement but the lines connect and appears to be one line drawing . When I try to duplicate the line tool guide it creates separate lines that are not connected and when i play the animation it plays as separate lines not one unison line guide . I hope I'm making sense .
Why are you people using the line tool to draw guides instead of using... actual guides?