If you have a broker plane handle (also called a tote) the normal solution is to glue it back together. It can be really hard to clamp though as it’s not a square shape, so here’s a little trick I use.
Simple apply your glue, hold the pieces together to get the bond started and wipe off the excess glue that squeezes out, then use the plane body and the screw that holds the handle in place as your clamp. Put the handle back into place on the body and tigten the screw up and it will clamp the two pieces together while the glue dries.
Make sure you don’t have excess glue on there though as it can stick to the screw and make it hard to remove later on.