I tried clicking right on "Project panel" -> New -> Folder and , after creating it I moved a header file, but it didn't work.
I tried also from "File" menu -> New-> Source Folder. But it didn't work
You need to make sure that the compiler can find the header (and source) files. If you add a new folder, you need to tell this the compiler.
You can find the settings in
Project > Properties > C/C++ Build > Settings > ColdFire Compiler > Input
Project > Properties > C/C++ Build > Settings > HCS08 Compiler Input
There you find settings for include file path (both system and user includes).
Hope that helps,
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