How to use C# with CesiumJS to display one or many GPS points?

Hallo,

I've a C# Windows Forms application which reads a set of images containing gps coordinates.
After extracting the gps data I can get them back with something like myImages.ElementAt(0).GetLat()

Now I would like to show thoose coorinates as "Bookmarks" on a map (like the Google-Earth Bookmarks).

How can I achieve this?
For displaying CesiumJS inside my form I'm using this code:

var test = new CefSharp.WinForms.ChromiumWebBrowser("http://…")
{
   Dock = DockStyle.Fill,
};
toolStripContainer1.ContentPanel.Controls.Add(test);

Drag and droping a .kml file on my Windows Form works - but I Need to achieve this programatically.

Thanks in advance
Karl