How to make the resignation date field read only for employees in Resign from Employment Page?

Summary:

On the Resign from Employment page, we have the following requirements:

Make the "Resignation Date" field read-only for employees — however, the system currently does not allow this field to be set as read-only.

Change the label of the field from “Resignation Date” to “Separation Date”.

Could anyone please suggest if there are any alternative approaches or workarounds available to achieve these requirements ?

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