Error 5 often points to USB stick issue or bad .iso download or creation.
See: Error While Installing Zorin OS - Zorin Help
Did you first check the SHA256 checksum of the downloaded .iso file against the Zorin website published value?
Did you try the USB stick in a different USB port?
Which USB creation tool did you use. If Balena Etcher, try a different tool after first reformatting the USB stick.
If you search the forum here using "error 5" you will see several threads on that subject.
I suggest you acquire some additional USB sticks. If only to cover potential faults in the one you do have.
I assume all you have is ZorinOS on your one USB stick.
I am not sure whether Windows wold have been erased prior to "error 5" occurrance. Others on the forum may know more about the installation sequence and whether or not Windows may be recoverable or truly wiped.
EDIT: Also have a look at this pre-installation advice: Before you install