hi!
I created a font and now i will make this font bold.
Is it possible to select all letters and let the programm calculate them to bold?? 
No. More to the point, why would you want it to? Any word processing program can calculate a bold for you. A program like this lets you create one. Bolds are not just thicker versions of regular typefaces, they have a style of their own, and you should really consider designing one from the ground up.