Suppose Congress tried to create new laws that violate the Constitution. Could the president and/or the Supreme Court block

Congress's actions? If so, how?

on the off chance that a president has an uncertainty about the lawfulness of a bit of enactment, he can arrange his authority to go to courts and record a case. In a definitive end, the US Supreme Court will manage looking into the issue.

Of course he can. If a president has a doubt about the constitutionality of a piece of legislation, he can order his official to go to courts and file a case. In the ultimate end, the US Supreme Court will rule on the case.