How do i add a structure properly?

I am having problems with adding a structure to my headerfile. So if i add a structure i get errors.

#include "CoreMinimal.h"
#include "GameFramework/HUD.h"
#include "MyHUD.generated.h"


    struct MyStructure{



class Game_API AMyHUD : public AHUD


if i would try to compile my code i get this errors:

Error (active) E0077 this declaration has no storage class or type specifier

Error MSB3075 The command ““Epic Games\UE_4.24\Engine\Build\BatchFiles\Build.bat” BookEditor Win64 Development -Project=“UE Projects.uproject” -WaitMutex -FromMsBuild” exited with code 5. Please verify that you have sufficient rights to run this command. Book C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\VC\VCTargets\Microsoft.MakeFile.Targets 44

UE4’s header parser probably expecting FMyStructure instead of just MyStructure since your using USTRUCT().

Thank you for your answer.
It still doesnt work … Sorry im pretty new to UE4 .
If i just add a structure without USTRUCT() i get the same errors. Am i missing something?