Do young men experience erectile dysfunction?

Yes. Yes, all males can experience erectile dysfunction. This is a multifactorial condition that can occur in any age group for various reasons. If this is a new finding or if the patient is very young, it would be appropriate to see your physician for a general workup as there may be physiological condition that may be treatable and correct the problem.
Erectile dysfunction. Yes, if they have hormonal imbalance, or using certain drugs, or have diabetes.