Question

how did the war between us and vietnam came to an end where did the peace treaty was signed

Answer 1

It came to end through the Paris Peace Accords (PPAs) signed in Paris.There are also many reasons how US stopped it's involvement some of the reasons are as:
The Congress passed a resolution which limits the president’s power to commit armed forces abroad without its consent and overrode the presidential veto..
The huge and Massive anti-war protests were held throughout the country against the US war effort in Vietnam.