How to request user coordinates on page load and pass in PHP?

Question

JavaScript

Hello. I'm trying to make a service using google maps. I want something at startup (either from a computer or from a phone), the map was set as accurately as possible at the user's location, and it is desirable that there be a label where it is located (as in a phone). So that when you open the site, it asks "The page is asking for your current location, allow it?". I found something on the Internet, but it only works from a PC, from a phone - it doesn’t ask for anything :( and it doesn’t show where I am approximately, it just puts the map in the center.