Will hyperventilating help you during an asthma attack?

No. Inducing hyperventilation is not the way to treat asthma. In fact, some asthmatics can start to hyperventilate with their asthma flares and make treating their asthma flares more difficult.
No.... During an asthma exacerbation, the airways are obstructed so breathing faster does not help the underlying problem. But, if the oxygen level drops, the brain will trigger the body to increase respirations (both rate and volume) in an effort to take in more oxygen. Treatment includes bronchodilator and steroid inhalers with more aggressive therapy if these are not enough.