easiest way to extract a frame?

[Jeff Herring]

put your cursor on the timeline where you want your fram to be. then select “composition” menu and then “Save Frame as” and you can select the format (jpg,tga,gif) that you perfer

or

put your cursor where you want the frame to be and press ctrl+alt+s

[David Johnson]

Or, get the free CopyImage plugin from https://www.obviousfx.com/
Then, put your cursor on the frame you want, Copy Image and paste into Photoshop of other program for editing.