Spotify is a music site available in many countries, but not everywhere. Proxies can allow access to this resource even if you are in a country where access is not yet available. But these are not all the useful features that can be used with Spotify proxy. It also reduces the time wasted downloading data by caching search history and allows you to remain anonymous to data collectors.
You can search for free proxies or use the services of one of the sellers. In any case, before using, you can use an IP database or online checker to test your proxy.