Formula text field to return ID of a user

#field #Formulasandfunctions 

Hello,

We have a record with Agent Name, ID, Supervisor and Manager. The field "ID" returns the ID of Agent Name. What I want to do is add another field called "Supervisor ID" which should return ID of the Supervisor of that specific Agent. I'm thinking of a formula text field with this logic:

ToText([ID] of [Supervisor])

What should be the appropriate formula for this?

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Isabel Gumanid
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