Once you have markers on the map, you can retrieve the Lat/Long coordinates through the API and use this to set the map’s center. You’ll first just need to determine which marker you wish to center on – I’ll leave that up to you.
// "marker" refers to the Marker object you wish to center on
var latLng = marker.getPosition(); // returns LatLng object
map.setCenter(latLng); // setCenter takes a LatLng object
Info windows are separate objects which are typically bound to a marker, so to open the info window you might do something like this (however it will depend on your code):
var infoWindow = marker.infoWindow; // retrieve the InfoWindow object
infoWindow.open(map); // Trigger the "open()" method
Hope this helps.