It's wrong to lie to your kids about Santa and tell them that he is real.
However it's okay to mention Santa and enjoy Santa but the kid should not be told he is real.
The kid should be told the truth about Santa and mention that he is not real but it's okay to know that he is there in imagination
But if you want to lie to your kid about Santa that is not all that bad and they will find out about him later on and they will not be harmed.
My parents lied about Santa to me and I turned out okay later on when I realized he was not real.