How to add a Column of TAX ID in sales order

how to add a Column of “CUSTOMER TAX ID” in sales order below customer’s order purchase date as shown in image.

You can make this by adding Custom Field
As follow:

Sir,

i have did the things that u have said but when i am trying to select the customer it is saying an error message as shown below:-

Error msg:
Wrong fieldname None in add_fetch configuration of custom script

Is this field tax_id available in Customer doctype. If not then you will have to create a custom field of the same name

i have add a custom field of customer tax id as shown in image but when i a trying to select the customer, the error message is showing up

Error msg:
Wrong fieldname None in add_fetch configuration of custom script

8c572ea43a4c89a3cc6cba054d1403517d89ea5c_1_689x337

i have add a custom field of customer tax id as shown in image but when i a trying to select the customer, the error message is showing up

Error msg:
Wrong fieldname None in add_fetch configuration of custom script

8c572ea43a4c89a3cc6cba054d1403517d89ea5c_1_689x337

tax id is already created but not showing and shows an error message while creating sales order and select for customer:-

Error msg:
Wrong fieldname None in add_fetch configuration of custom script

Oh, I am sorry for that
I am working on old version … in your version you must put customer.tax_id in Fetch From not in the Options