They also gained independence and were very lucky to defeat one of the world's largest economies. They also elected Washington as the first President. They created the Constitution of The United States of America.
The reason the Constitution was made is that we have independence.
When the war was over Benedict Arnold and General Cornwallis and their troops surrendered. The patriots won the war and received independence.
When Washington arrived in Saratoga he was shocked to see the devastation. Washington had to spend a very harsh and brutal winter at Valley Forge. The French joined the war against the British.
A joint French and American force trapped the British