You can use Seeker in Seek Data menu. Then, load the area of interest by selecting any projected grid in your project. Next, select Results and select the STRM Topography folder from the Geosoft Public Dap Server to download the topography grid of your area.
After the topography grid is downloaded you can extract from it the elevations of a set of points in your database. This can be achieved through adding a new channel named Topography to your database and then using Sample a Grid option in the Grid and Image menu > Utilities.