Male 22. is cardio exercise at 130bpm for 40mins a day enough to build stamina and heart benefits?

Yes but..: Yes, that's good but, unless u r just starting, your best training zone may be a little higher. Look up aerobic training zones online + you'll see how to calculate target heart rate. To build speed + endurance, interval training (with short sprints added to an aerobic workout) is popular again. And don't forget to cross train a bit (mix up run, bike, swim, elliptical) to avoid overuse injury.