My son had a level 2 laminectomy which required revision surgery due to post surgical staph infect. He came home today. No covering on wound ok?

Yes. This should allow the surgical site to remain clean and dry. The surgeon will have given instructions as to how to shower or bathe with the incision.
Yes, OK. But keep it clean. Ok to cover loosely for comfort if there are stitches or staples but not necessary.