Malware on parked domain

To start, I’m very new to building websites, and I’m learning as I go along. So please excuse any naivety on my behalf. I have a parked domain that is infected with malware. However, the primary domain seems to come up clean when scanned.

Am I able to just delete the parked domain, then add the parked domain again?

If not, why wouldn’t this work, and what would be my best course of action?