Congress did not have the power to enforce laws under the Articles of confederation true or false?

Neither Congress nor the President has the power to enforce laws. Congress makes laws; the President can propose, approve or veto a bill. The Department of Justice, within of the Executive Branch, has the power to enforce Federal Laws. But to address your question about the Articles of Confederation, the answer is no in both cases: making and enforcing. Those privileges were reserved to the states. And as a matter of interest, in the Articles, the President was only a figurehead, overseeing sessions of the proposed single-house Congress.