Updating Ue4

The project could not be compiled. Would you like to open it in Visual Studio?

Running C:/Program Files/Epic Games/UE_4.21/Engine/Binaries/DotNET/UnrealBuildTool.exe Development Win64 -Project="C:/Users/Cinnnika Z/Documents/Unreal Projects/SuperNinjinMARS/SuperNinjinMARS.uproject" -TargetType=Editor -Progress -NoHotReloadFromIDE
Creating makefile for SuperNinjinMARSEditor (no existing makefile)
Performing full C++ include scan (no include cache file)
Using Visual Studio 2017 14.16.27023 toolchain (C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023) and Windows 10.0.17763.0 SDK (C:\Program Files (x86)\Windows Kits\10).
@progress push 5%
Parsing headers for SuperNinjinMARSEditor
  Running UnrealHeaderTool "C:\Users\Cinnnika Z\Documents\Unreal Projects\SuperNinjinMARS\SuperNinjinMARS.uproject" "C:\Users\Cinnnika Z\Documents\Unreal Projects\SuperNinjinMARS\Intermediate\Build\Win64\SuperNinjinMARSEditor\Development\SuperNinjinMARSEditor.uhtmanifest" -LogCmds="loginit warning, logexit warning, logdatabase error" -Unattended -WarningsAsErrors -installed
C:/Users/Cinnnika Z/Documents/Unreal Projects/SuperNinjinMARS/Source/SuperNinjinMARS/BaseCharacter.h(18): Error: #include found after .generated.h file - the .generated.h file should always be the last #include in a header
Error: UnrealHeaderTool failed for target 'SuperNinjinMARSEditor' (platform: Win64, module info: C:\Users\Cinnnika Z\Documents\Unreal Projects\SuperNinjinMARS\Intermediate\Build\Win64\SuperNinjinMARSEditor\Development\SuperNinjinMARSEditor.uhtmanifest, exit code: OtherCompilationError (5)).

As stated in the error, open up BaseCharacter.h and make sure #include BaseCharacter.generated.h is the last include

according to #8 you have some include after your .generate.h file. make sure moving it before that
what ever ends with .generate.h should always be the last header file

C:/Users/Cinnnika Z/Documents/Unreal Projects/SuperNinjinMARS/Source/SuperNinjinMARS/BaseCharacter.h(18): Error: #include found after .generated.h file - the .generated.h file should always be the last #include in a header

Thank you but it is.
???

As i told above, you have includes after BaseCharacter.h
i can see them in your file in lines 18 and 19. both are excessive as they are duplicate of lines 6 and 7. delete them and this error should not occur.

PS : although you can add include anywhere in your file, try to avoid this practice as much as possible and only add them at the beginning. obviously there are exceptions that force you to do so