This would just be creating a graphic on the map at the specified coordinate. Check out the Intro to graphics sample app and follow what is done for the point graphic. Instead of hard coding the longitude, latitude of the point, populate those values from the input boxes shown in your screenshot.
You should also check out the sketch widget in case that is a better fit for your app.
My actual requirement is to make a point on the Map based on the X,Y values entered. How can i achieve this?
I know how to use Sketch for Polygon, Polyline, etc. But, i want this feature.
Screenshot is the Design given based on which we need to implement.
Sorry if my original message was not clear enough. Here's an outline of what you need to code.
The "Intro to Graphics" sample app demonstrates code for steps 4 - 7.