How to put warning on Last Working Day field like Termination Date

Hi Experts

On Termination date we have by default warning if we select date before notice period end like this.

We need similar kind of warning on Last Working Day field.

With which condition we can achieve this on Validation Rule or do we need to have any other setup?
Where we can find setup of this seeded warning delivered by oracle?
Can we apply same from there on other field?

Thanks