Yes, neon tetras can live with guppies. Neon tetras and guppies make good tank mates, especially if their owner keeps them happy by providing them with their ideal living conditions.
In addition, neon tetras and guppies are easy to take care of because they eat the same food, are peaceful fish, and both require plenty of swimming space. Make sure not to overcrowd your tank, and to provide your fish with plenty of plants to keep them entertained.
Also, note that you should have a minimum of six neon tetras in your tank for them to do well.