Keep in mind that if someone sold you a password locked device and they do not know the password it may be stolen property. As such, if the authorities find the thief and trace the sale they could seize it from you. So the first thing I would do is contact the seller and ask the password. If they do not know it I would ask to return for a refund. Best not to get involved.

If you cannot or choose not to return it then you need to determine if it is disk encryption or a BIOS password. If it is an encrypted disk then just low level format it. You don't need someone else's data anyway. If it is a BIOS password that is stored on the motherboard you would have to convince ASUS support that you are the legitimate owner or solder a new chip onto the board.

either bruteforce the password (can take half a second upto,, maybe years) or format it somehow
or yea call the police
try the police first, but the police will probably tell you to contact ebay first (happen with me)

You can ignore WinOS logon and BitLocker/encryption passwords. Just nuke and pave the drive with a fresh OS. Of course all password-protected data will be lost.

You can sometimes erase firmware/BIOS HDD password. Clear CMOS, pull the battery, etc.
But if there's a firmware password on the drive's embedded hardware then the drive will simply be locked out, forever. You can hire a data recovery service ... they basically use forensic data methods or actually transplant the drive logic board and media platters into identical/modified drive models ... they can recover/copy whatever data's on it (sometimes decrypted, sometimes not) but they can't "unlock" the drive itself.

You could buy a new HDD. Or better yet, a new SDD.

or go visit the russian forum CS.RIN.RU and ask around there
thats where a lot off ummmm, people with this expertise hang out