Conversation so far:
who has to ratify a treaty made by the president
The Constitution provides that the president shall have Power, by and with the Advice and Consent of the Senate, to make Treaties, provided two-thirds of the Senators present concur.“
what part of the constitution says that the president can make treaties
The Treaty Clause is part of Article II, Section 2, Clause 2 of the United States Constitution.
does the constitution say anything about international policy
The U.S. Constitution gives much of the foreign policy decision-making to the presidency.
what kind of foreign policy decisions does the president make
The president appoints ambassadors, ministers, and consuls (subject to confirmation by the Senate) and receives foreign ambassadors and other public officials.

Question: what about the power to declare war
Self-contained rewrite: does the president have the power to declare war