How to update identity Column table without changing Identity

 Create replicate table Using script out

Then Insert all data to new create column

Insert INTO [dbo].[TestBRZ] SELECT *  FROm [dbo].[Subaru_BRZ]

Then get the script update table A using Script out

After that insert data to table A  using Proper column

SET IDENTITY_INSERT [dbo].[Subaru_BRZ] ON

INSERT INTO  [dbo].[Subaru_BRZ] (carID,milage)

SELECT carID,milage

From [dbo].[TestBRZ]

SET IDENTITY_INSERT [dbo].[Subaru_BRZ] OFF

UPDATE [dbo].[Subaru_BRZ]

SET color  = 'B'

WHERE carID = 3

Done!