what is Vocaloid?
Vocaloid is a singing voice synthesizer software which is a project led by Kenmochi Hideki at the Pompeu Fabra University in Barcelona, Spain, in 2000 and was not originally intended to be a full commercial project. Vocaloid also comes in many different languages which is Japanese, English, Korean, Spanish, Chinese, and Catalan.
You can buy Vocaloid on the official website
if you wanna learn more about Vocaloid go to the wiki that's on Fandom