Just as their name suggests, these devices can only aid your hearing, what ever its condition. They can't restore hearing nor retard the progression of nerve deafness.
There are two things to know right from the start. One, hearing instruments don't sound the same as having your old hearing. And two, adjusting to wearing them takes time. Just like getting comfortable with a pair of bifocals, you may experience some frustration at first, but it will pass in time.