Traditional porcelain veneers are not reversible, because they require permanently altering your tooth enamel. Should you choose these veneers, you will always have to keep your teeth covered. .5 mm of your enamel is shaven down and this puts your teeth at increased risk of damage, cavities, and infections if not covered.
They will also look very strange without your veneers. However, you can choose reversible composite resin veneers or Lumineers which are not permanent.