>Is Possible to Merge Two Columns of a Grid, to Give Common Heading. Like we do in Excel.

I believe, it is possible, but when you code on your own.
Details on what to do and how depend on what is the recordsource for grid, whether you want just to display the result, or make changes in the underlying tables, etc.

One of the solutions is to remove the grid header, and to use labels instead.
Sure, several limitations follow ...