The diagram shows a beam of electrons about to enter a magnetic field. The direction of the field is into the page. What will be the direction of the deflection, if any beam passes through the field?

The direction of current is from left to right as the electron beam enters from left to right and the magnetic field is into the page.

According to the Fleming’s left hand rule the force is perpendicular to the flow of current and is in its left side. So electron beam deflects towards bottom of the page. As shown in the figure below.