Is asking for a day off as a temp good?

You don’t have fixed schedule so why would it matter?

Unless you already picked up the shift

Nope. Usually companies hire permanent staff from within. I started at Harvard Pilgrim as a temp and had a car accident on my way in, on my first day. My new manager looked at me as though I was a low life. I would NEVER have asked her for a day off...jobs were really scarce!

I worked extra hard after that, and applied for a permanent position, and they hired me!

Yes, they don't care how long you take off, just come back. Or don't.

if you dont want the job maybe idk

Yes