“If I delete a virus from my anti-virus will it remove it from my computer or does it release it back on the computer?”
When you delete the virus from the anti-virus quarantine it will be removed from the computer completely.
When a virus is quarantined the anti-virus program encrypts the virus with a code which makes it useless and non-threatening. One of the major reasons it’s quarantined and not removed immediately is because of false positives. Quarantining prevents the anti-virus program from removing any kind of critical computer file which it may need to operate properly. The user could easily restore the file from the quarantine vault preventing any sort of damage.