while i was drawing a scene in 1920 x 1080 two boxes appeared at the side and pushed my focus away when i went over them and somehow the resolution for the canvas is now 1920 x 1661. how do I shink the canvas down back to 1080p instead of this odd resolution?

I think you clicked "extend the canvas" arrow icon.(It's there so that users can extend the canvas - "pseudo-infinite" canvas)
To bring the canvas back to the original size, use image->resize canvas, specifying the correct anchor(I guess it's right or left depends on the direction you extended)

Details in this section of the manual:
https://userbase.kde.org/Krita/Manual/W ... the_canvas