The general advice is no - chickens are social animals and are stimulated by each other’s company. Just watch a group following each other around, or roosting, scratching and resting together, and you’ll get the picture.
Having said that, a chicken has a brain programmed to do what a chicken has to do - and even when there are no other birds around, a hen will perch, lay, eat, sleep, scratch and forage as normal. They don’t need others to teach them what to do.
a Rhode Island Red - looking for company?
Keeping Just One Hen
Sometimes you may be in a situation where only one hen has survived from a group of point-of-lay hens you bought a few years earlier. In this case there’s no absolute need to rush out and buy her more companions - it’s usually best to wait for the next season, when more point-of-lay hens (i.e. birds that are no longer chicksm but have not yet laid their first eggs) are available.
There are actually a few counties in the USA where one hen is the limit allowed by local law. Luckily for UK chicken keepers, there are no such restrictions. So, unless you have an old hen who has lost her original flock, always keep chickens with a minimum of two birds.