Currently, Glockenspiel refers to a metallophone. This is a percussion instrument that has a tuned metal sound plate and is struck with the sticks.
In fact, in the past, there was a Glockenspiel played on the keyboard. The current Glockenspiel has only its sound plate remaining. Moreover, the keyboard-type Glockenspiel appeared before Celesta.
Originally “glocken” was a bell. When you go to Europe, there is a large bell in a church, but around the 17th century, a small version of the bell was adjusted to various types of pitches and prepared for about three octaves.