Unity Error when building game

Whenever I try to build my game I get error codes:
Assets/HolyShift/Scripts/CheckForStandardAssets.cs(4,7): error CS0246: The type or namespace name `UnityEditor' could not be found. Are you missing an assembly reference?

Assets/Standard Assets/Utility/SimpleActivatorMenu.cs(10,16): warning CS0618: `UnityEngine.GUIText' is obsolete: `This component is part of the legacy UI system and will be removed in a future release.'

Assets/Standard Assets/Utility/ForcedReset.cs(6,27): warning CS0618: `UnityEngine.GUITexture' is obsolete: `This component is part of the legacy UI system and will be removed in a future release.'

Error building Player because scripts had compiler errors

Build completed with a result of 'Failed'
UnityEngine.GUIUtilityrocessEvent(Int32, IntPtr)

UnityEditor.BuildPlayerWindow+BuildMethodException: 2 errors
at UnityEditor.BuildPlayerWindow+DefaultBuildMethods.BuildPlayer (BuildPlayerOptions options) [0x00207] in C:\buildslave\unity\build\Editor\Mono\BuildPlayerWindowBuildMethods.cs:172
at UnityEditor.BuildPlayerWindow.CallBuildMethods (Boolean askForBuildLocation, BuildOptions defaultBuildOptions) [0x00050] in C:\buildslave\unity\build\Editor\Mono\BuildPlayerWindowBuildMethods.cs:83
UnityEngine.GUIUtilityrocessEvent(Int32, IntPtr)

You are trying to create a MonoBehaviour using the 'new' keyword. This is not allowed. MonoBehaviours can only be added using AddComponent(). Alternatively, your script can inherit from ScriptableObject or no base class at all
UnityEngine.MonoBehaviour:.ctor()
UnityStandardAssets.Utility.PlatformSpecificContent:.ctor() (at Assets/Standard Assets/Utility/PlatformSpecificContent.cs:29)
UnityEditor.EditorUserBuildSettings:set_selectedStandaloneTarget(BuildTarget)
DesktopStandaloneBuildWindowExtension:ShowPlatformBuildOptions() (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/DesktopStandaloneBuildWindow.cs:155)
UnityEditor.PopupCallbackInfo:SetEnumValueDelegate(Object, String[], Int32)

NullReferenceException
UnityStandardAssets.CrossPlatformInput.MobileControlRig.EnableControlRig (Boolean enabled) (at Assets/Standard Assets/CrossPlatformInput/Scripts/MobileControlRig.cs:89)
UnityStandardAssets.CrossPlatformInput.MobileControlRig.CheckEnableControlRig () (at Assets/Standard Assets/CrossPlatformInput/Scripts/MobileControlRig.cs:82)
UnityStandardAssets.CrossPlatformInput.MobileControlRig.OnActiveBuildTargetChanged (BuildTarget previousTarget, BuildTarget newTarget) (at Assets/Standard Assets/CrossPlatformInput/Scripts/MobileControlRig.cs:98)
UnityEditor.Build.BuildPipelineInterfaces.OnActiveBuildTargetChanged (BuildTarget previousPlatform, BuildTarget newPlatform) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/BuildPipelineInterfaces.cs:345)
UnityEditor.EditorUserBuildSettings:set_selectedStandaloneTarget(BuildTarget)
DesktopStandaloneBuildWindowExtension:ShowPlatformBuildOptions() (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/DesktopStandaloneBuildWindow.cs:155)
UnityEditor.PopupCallbackInfo:SetEnumValueDelegate(Object, String[], Int32)

Assertion failed: Assertion failed on expression: 'm_CurrentEntriesPtr != NULL && m_IsGettingEntries'
UnityEngine.GUIUtilityrocessEvent(Int32, IntPtr)

Please help I could also collab so you can see for yourself.

 

You need to import the standard assets package.

 

Ok let me try

 

It's already imported

 

The type or namespace name `UnityEditor' could not be found. Are you missing an assembly reference?

in the script with this error:
#if UNITY_EDITOR
using UnityEditor;
#endif


with NullReferenceException
UnityStandardAssets.CrossPlatformInput.MobileControlRig.EnableControlRig

the script has error in the namespace,

must be namespace Standard_Assets.CrossPlatformInput.Scripts

Other erros I don't know becouse i haven't it

(sorry my english xD)