Many snails will not eat healthy plants just the dying edges or dying plants to clean them up.
Safe ones would be Mystery snails (Pomacea Diffusa also previously named Bridgesii) some times called Apple Snails (which may eat plants, Pomacea canaliculata, invasive, common name the channeled applesnail).
Ramshorns (Planorbis rubrum) in many different colors.
But the gold and dark striped Giant ramshorn snail (Marisa cornuarietis) may eat plants.
Pond aka Bladder snails Lymnaea stagnalis are good clean up crew but lots of people dislike them, as they reproduce quickly in some tanks.
Assassin Snail is a small snail which can kill and eat nuisance snails for you. Some thought is that they kill their prey with neurotoxin... Can take down fairly large snails.
Those above reproduce easily in FW
Then there are Nerite snails of a variety of colors, patterns and shell features like spikes - very cool!!! These do not reproduce in FW
though they lay eggs, they need brackish water for viability.