No, Congress delegated that authority by law (Title 10) to the Secretary of Defense. The President must approve the SecDef's deployment plans but he doesn't order the SecDef to deploy or delegate authority to the SecDef to deploy.
So what you are saying the is that the secretary of defense can send troops anywhere he wants to as long as the president approves it, even Iran?
and that those orders from the Secretary of Defense don’t come from the president since he is not in the chain of command because he only approves them...
Like when Truman only approved the atomic bombing of Hiroshima, he did not actually order it done he merely approved of it someone else was actually responsible for the order to drop the bomb...