After a bill has gone through both houses of congress where does it go?

At this point, the bill is sent to the President. If he or she signs it, the bill becomes law. If the President vetoes the bill, it is sent back to congress. Now, it will take a 2/3 vote in both the Senate and House of Representatives to override the President's veto and make the bill a law. (It is very hard to get a 2/3 vote.) There is also a pocket veto where the President does nothing and just lets the bill die. (Look up pocket veto.)