Go to the menu bar and open View
Enable Show Canvas Edges
Enable Wrap Around Mode if you want to see repeated canvas edges
Disable Full Screen Mode if it is hiding the interface
Use the zoom out shortcut to see more of the workspace
Press Tab to hide or show panels and free up space
Drag the canvas with the middle mouse button or spacebar
Use the Navigator docker to move around the canvas
Increase the workspace size or move the Krita window to a larger monitor
Check that the canvas is not maximized inside a docked view
Reset the workspace layout if panels are blocking the view