Name of withholding field

in this example what should be the name of withholding field?

@uzair94, what are you asking about? This topic is about calculations in custom fields. It is not related to withholding in any way.

iam just asking for technical name of existing withholding tax field to call the data of that field

Your question was moved to a new topic. Please do not divert topics with unrelated questions.

The answer to your question depends on where in the program you are referring to. In Batch Create? Batch Update? In themes? On a transaction entry form?

in theme

It is part of the totals array variable. When you write themes, you are on your own.