Plotting (or reading out) individual pixels on a Canvas (or an Image interface) is possible; just index or assign through them with an (x,y) pair as if they were a list or dictionary.
Plotting a large number of pixels will be fairly slow, since doing so will force the Lil interpreter to do a large number of serial operations. Both canvases and images provide a variety of higher-level methods for scaling, transforming, and drawing which operate upon pixels in bulk, and should generally be preferred, especially if the goal is any sort of realtime animation.