Sounds bad news,(sorry)try and fit new cam belt or turn engine over by
hand first you will know then if the valves have hit the pistons,if so
the valves will be bent and that means new head or just remove and have
a look to see what is what.

Maybe the water pump failed??? And it's snapped your cam belt , the cam
belt drives that and it's always best to change it when you renew your
cam belt, try filling it up with water and see if it's running out of
the timing cover, take the top cover off and check the rocker arms, I
heard that they will bend or snap before they put a valve through a
piston so maybe you might be lucky , good luck anyway