How can I add listing Coordinates so that it gets showed on Google map? What do I need to do so?

Install google maps plugin. No coordinates are required, it is identified based on country, region and city

Dear frosticek,
Sorry if I have not been clear with my request.   
I already installed google maps and the general location is identified based on country, city. 

However, I need to provide the user with the ability to enter the House, Apartment, etc. GPS Coordinates (i.e. latitude and altitude) for their listings to be reflected on google map. Or to drag the red marker on Google map to the exact listing location, Sample photo is provided.

Thanks for your help

@alsharif
Take a look to plugin code to see what everything it accept:
function insert_geo_location($item) {
        $itemId = $item['pk_i_id'];
        $aItem = Item::newInstance()->findByPrimaryKey($itemId);
        $sAddress = (isset($aItem['s_address']) ? $aItem['s_address'] : '');
        $sCity = (isset($aItem['s_city']) ? $aItem['s_city'] : '');
        $sRegion = (isset($aItem['s_region']) ? $aItem['s_region'] : '');
        $sCountry = (isset($aItem['s_country']) ? $aItem['s_country'] : '');
        $address = sprintf('%s, %s, %s, %s', $sAddress, $sCity, $sRegion, $sCountry);
        $response = osc_file_get_contents(sprintf('http://maps.googleapis.com/maps/api/geocode/json?address=%s', urlencode($address)));
        $jsonResponse = json_decode($response);
       
        if (isset($jsonResponse->results[0]->geometry->location) && count($jsonResponse->results[0]->geometry->location) > 0) {
        $location = $jsonResponse->results[0]->geometry->location;
        $lat = $location->lat;
        $lng = $location->lng;
       
            ItemLocation::newInstance()->update (array('d_coord_lat' => $lat
                                                      ,'d_coord_long' => $lng)
                                                ,array('fk_i_item_id' => $itemId));
        }
    }


Dear Frosticek,
Please bear with me as I am still learning. 
I see that the function takes Latitude and Altitude, but how do I integrate it within your theme and how do I pass lat & lng values to the function.

I appreciate responding to my query.  Many thanks

A gentle reminder to the question that I’ve raised. Thanks

@Alsharif
I recommend to check documentation for google maps API, I do not know that information as well.

A gentle reminder to the question that I’ve raised. Thanks

Did youu find an answer, because i faced the same issue the Coordinat elat long didn't save inta Data base