I’ve heard that you can draw off the canvas, but I can’t find how to do that. Could someone let m know please?
Maybe you are thinking of MyPaint, which has basically infinite canvas? I don’t think Krita has such feature.
Krita’s layers are infinite in size, limited by the amount of RAM you have and the content painted on them.
The canvas is a rectangular ‘view-hole’ onto the layers.
If you paint on a layer and take the brush beyond the canvas edges, it will paint on the layer off-canvas.
You can try this and then use the Move tool to move off-canvas content back onto the canvas area.
There are limitations in some cases where you transform some types of content so it goes off-canvas but I’ve forgotten the details of that. You’d soon notice if you tried it.
If you want to deliberately have off-canvas content, which is useful/essential for certain types of animation involving animated transform masks (and also other things you can do) then you can plan for this by Resizing the canvas (Image → Resize Canvas) to show the off-canvas area so you can work on it and then later you can Resize it back to the intended final ‘presentation’ size.