Using vanilla Construct 2 (as in without plugins etc) I do this using CanvasSnapshot. Add the action 'Snapshot canvas', which is found in 'System'. You then need to use the corresponding condition, which is 'On canvas snapshot' (also found under 'System' to collect the image. At this pint the image is stored in the expression 'CanvasSnapshot'. You can store this data in a sprite, tilemap, or tiled background by using the action 'Set frame from URL' and entering 'CanvasSnapshot' as the URL.
Beware using this alongside save/load, as the image will be lost. Store the expression 'CanvasSnapshot' into a variable on the sprite, and have the sprite update its frame from the URL provided in the variable when the game loads.