Congress is responsible for editing, discussing and passing the bill. Both houses of Congress have to agree on the same version of the final bill until it goes to the President.
The President has three options, he can veto the bill, rejecting it and making it return to Congress with the reasons for the veto. Congress in this case, can override the veto with a 2/3 vote.
If the President agrees with the bill, he can sign and approve it, only with his signature the bill with becoming a law.
