What do you need to auto-call a phone and play a voice message there?

Question

PHP

Hello experts!
It is necessary to call the phone from the site in php on an event and, after picking up the handset, play a sound file with a voice there. After an hour of googling, I had a vague mess in my head from the words: voip, asterisk, ip telephony ..
But I don’t know what exactly to do. How should the chain look like? I put asterisk on a dedicated server, use php to work with it, and asterisk needs to be connected to a voip provider?
How to do all this, can you tell me in more detail?