Populating email in reply from field when type of user is internal on finance workspace form

[Community Alums]

Hi,

I am trying to Populate email id under reply from field only when type of user is internal else It should not be populated.

How can I achieve this on finance workspace form not on portal?

Also I want to change by default value of email id populated  under reply form field when type of user is internal.

Thanks in advance!