car not starting

My 2001 impala had starting overheating....
It got to the point where I'd have to pull over
n let it cool n I'd pour water into it. I
attempted to drive one day n it sounded like
a diesel truck n turned off. I was told it was
my water pump... I fixed that n now it won't
turn over unless I get a jump but it won't
start completely... For the first time ever a
slight amount of antifreeze popped out the
radiator when I tried to start it n a lil smoke.
But  this happened after it broke down. What
is the problem n what do I do? Help me!!!!!