It's not as simple as "X will make you lose weight or not." Caloric deficit depends on both your intake and expenditure. You can out-eat almost any exercise regime so a somewhat healthy diet and reasonable portion sizes are always going to be important.

Active VR games are a legitimate cardio workout. Sites like https://www.vrfitnessinsider.com/reviews/ have real data if you don't believe me.

As for duration, I've seen people (including myself) happily play Beat Saber for hours who don't last 10 miserable minutes on a treadmill.