The executable file name is specified, without extension, in the .csproj file:
<AssemblyName>my_program</AssemblyName>
To identify the project as an executable rather than e.g. a library, it should also have:
<OutputType>WinExe</OutputType>
Note that it's possible that the executable has been renamed after it was built. Executables often, but not always, have their original file name stored with their version info. You can check this in the window explorer:
https://i.stack.imgur.com/YOGRS.png[
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