 I know that presidents can take executive action, but if they don't have the influence to back it up with the support of Congress, Congress can override it. Presidents can't just randomly enact legislation, at least they're not supposed to by the Constitution, although we live in up until the Chevron decision, thankfully, was overturned by the Supreme Court. The idea of executive agency is just making up legislation under the guise of rules, but for the most part, presidents have to just influence people.