How to get a request without refreshing the page?

Question

PHP

I am writing my first bot for VK, its task at the moment is to respond to an incoming message.
I use the messages.get method (returns a list of incoming or outgoing personal messages of the current user), I find a message in it, and I answer using the messages.send method. But the trouble is that when I try to find out if a new message has arrived, I have to refresh the page.
Question: how to find out about an incoming message without refreshing the page? Here it came to me in VK, the bot immediately processed and answered.

Answer 1

Yuzai longpoll, for this it was created

Answer 2

cron?
js &&setInterval();