Hi, @perminder_sandh 
Welcome to the Canvas Community! The instructions for unpublishing a course are in the Unpublish Course section of How do I publish a course? ; as that section explains, "Once your course contains a graded submission, you can no longer unpublish your course." The usual way of removing availability of a course is to conclude the course (How do I conclude a course at the end of a term as an instructor?), but before doing so, please check with your local Canvas admin to see how they manage course dates for instructors.
