Is there any APIs available to install the driver for my device say for example (PNPC031) from the driverstore or from the inf folder?
Triggering plug-and-play detection for devices should install the driver for your device from the inf directory/driver store - if it finds a matching driver. Check out the CM_Reenumerate_DevNode_Ex API: http://msdn.microsoft.com/en-us/library/windows/hardware/ff539766(v=vs.85).aspx
If you know the path of your INF file you can install it with the Setup API: http://msdn.microsoft.com/en-us/library/aa377398(v=vs.85).aspx