rest or relax?

No conversation.

Hello everyone. Is it correct if I fill the blank in the following conversation with "rest or relax"?
Both are correct for the blank?

Teacher: Are you OK?
Student: No, I’m not. I have a headache.
Teacher:

John: I am so stressed out. Today started off badly. My six-year-old threw a hissy fit and didn't want to go to school. The traffic was horrid and someone cut me off, giving me a finger, so I was late for work, and my manager royally chewed me out. And that was just the beginning.
Betty: You just need to -------------.

sunny123 Are both correct for the blank?

One is better than the other.

Ok, then probably you mean both are correct for the blank but one is better than the other. Right?
and also let me know which one is better?

sunny123Ok, then probably you mean both are correct for the blank but one is better than the other. Right?and also let me know which one is better?

Yes. But which would you pick?
You have two verbs and two conversations, one verb for each conversation.

sunny123 sore eyes,

I'm not sure what that means, coming from an observer especially.

Mister Micawber sunny123 sore eyes,I'm not sure what that means, coming from an observer especially.

sore eyes =

Mister MicawberI'm not sure what that means, coming from an observer especially.

Yes, it should be "red, watery eyes."

The student certainly would not be a "sight for sore eyes."

sunny123sore eyes = link

That is just photos; it does not show the use of the phrase in any context.