I have a 8 year old son who was very asthmatic, and his doctor mostly wants him to stay in door. is this the right way to handle asthma?

Asthma: You wrote "was" very asthmatic. He "is" or "was"? This is not the way we treat asthma, especially in an active 8 year-old. Sounds like you need a 2nd opinion or should start by seeing an allergist who treats asthma in the pediatric population.

No need to stay insi: Your son does not need to stay inside. He should have a quick relief inhaler to use when short of breath, and if he has symptoms morethan twice a week he should start on a maintenance low dose steroid inhaler, or, if his asthmaismoresevere, a combination low dose steroid /longacting bronchodilator inhaler. I would encourage him to go out and play sports when his asthma is well-controlled with med.