Select the plane (Table object). Enter Edit mode, and select the outer row
vertices. In Side view, Extrude up to make the table sides.
Take the habit of give your objects (and all BLENDER data) explicit names.
This is very helpful.
With the vertices still selected, in Top view, Extrude one more time, and
Scale a bit, to make a little border. Now select the low left vertex ( see
image above) and place the cursor there, Shift-S keys, Snapp-Curs to Sel.
In Front view, press the little target button in the icons bar (that will
make the cursor the center of the actions) or do dot key, select the entire
low row, and rotate it a bit, like the image above. With this shape, when
the ball "get out" of game and came down the table, she will slide
to the restart position.
In Top view, add a Plane, and Scale it accordingly to the table dimensions,
to close it (that will be the pinball glass).