According to the declaration of independence what is the effect of declaring independence from Great Britain

The Declaration summarized the colonists' motivations for seeking independence. By declaring themselves an independent nation, the American colonists were able to confirm an official alliance with the Government of France and obtain French assistance in the war against Great Britain..

congress also has implied powers, which derive from the necessary and proper clause of the constitution and permit congress "to make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states.