My advice: make sure you pick an over-the-counter hearing aid that uses the information from your hearing test in the fitting process. If you have never had a hearing test, see a hearing care professional first.
If you don’t have access to a hearing care professional for a hearing test, you can use online apps such as hearWHO and Mimi. Keep in mind online tests may be designed primarily to initially program hearing aids and are not intended as a diagnostic evaluation to identify hearing or otologic disorders. If the results show a difference between your ears, please see a hearing care professional! Your ears deserve it! And so do you.