So when someone registers, they will type in their address, right ?
Your server will then receive that address, store it in your database.
Then you want to display a map with a marker for that address.
so you need
- a web form and an underlying database
- a geocoder, e.g.Nominatim which translates the address to lat/lon
- and some display technology for the map and the marker. This can be achieved with Leaftlet or OpenLayers Javascript libraries.
I doubt that you can accomplish this all if you are not a programmer.