Salesforce - Validation Rule (Based on a particular picklist value, make a field required.)

This is only for Admin beginners.
This video shows :
How to make a field required based on a particular picklist value.

[@chinmaypanda7885]

This knowledge helped me to overcome the trouble Thank you 👍

[@dineshmehetre9089]

Thank You...

[@konasravani2218]

Here in this video the field is coming by default without bothering the picklist value we are selecting but is it possible to display the aadhar no field only after selecting specific picklist value any idea?

[@ramudharmavaram2672]

how can we understand without a voice?