Do inhalers work to cover up the problem or help the lungs heal?

The former. Inhalers help control symptoms, but they do not induce healing. There are a number of therapies and agents that can help the body heal, including the lungs. The first thing to do is find the causes of the lung problems, then work to reverse them.
Yes. Assuming you're talking about copd, inhalers such as beta agonists, steroid inhalers, and anticholinergics treat and prevent the inflammation that leads to worsening of the COPD issue. They do not cure or reverse copd.