To get glasses, you will need to go and see an optician for your eyes to be tested. The optician will then decide if you need the glasses and also the type. The lenses will be stated but you can choose the frames that you want. There are also aesthetic glasses which you can buy to wear so that you improve your appearance. There are stores that sell such glasses with no power with a wide variety to choose from.
If you just need or want reading glasses you can get them anywhere- drug stores, retails like Walmart, book stores, etc. If you want or need presciption glasses you have to go to an optometrist for an eye exam then purchase both lenses and frames, which is not cheap.