Generally when we speak about veneers we are typically referring to "porcelain veneers". Veneer really means "to cover or change the front or outside". It is possible to have composite veneers, but generally that is referred to as bonding.
There are a number of types of porcelain veneers-that's where a great cosmetic dentist is necessary. Let them know what you want to change in your smile and tell them about what your concerns are. Then the cosmetic dentist can help guide you to the right veneer option to create those results.
One of the concerns I have in cosmetic dentistry is that too many brands get promoted and it is confusing to patients about what to realistically expect. Send some time thinking about what change you want and what your expectations are, and then instead of researching veneers, spend some extra time really studying cosmetic dentists. Look for before and after photos. Look for someone who looks like you. Study the result, look for reviews. Use all of this together to make your final choice.
A solid partnership with the right cosmetic dentist will create the results you are dreaming of!