I bought Toshiba Portege laptop and when you turn it on it the Toshiba logo comes on then a screen comes up asking for a password, it doesn’t say what the password is for. It just shows Password = and that is it. I replaced the HHD but it hasn’t made a difference.

This is not the hard drive password, this is the BIOS password.
If you are not sure witch password the laptop is asking for, remove the hard dive and turn on the laptop. If you can enter the BIOS setup menu when the hard dive is removed, it was asking for the hard drive password. If the laptop still asking for the password even when the hard drive is removed, it’s asking for the BIOS password.
Removing the BIOS password from newer Portege laptops could be a pain. For example, in order to remove the BIOS password from Portege A100, M100, M200, R100 you’ll have to take it to the authorized repair center. The authorized technician will have to call Toshiba and get a special code. Only after entering this special code you can clear the BIOS password.

You can remove the BIOS password from older Toshiba laptop with a special parallel plug witch you can make at home.
If you set and forgot the hard drive password, most likely you will not be able to recover it. You’ll have to replace the hard drive. I’ve seen some HDD password recovery software on the internet but I’m not sure if it works, never tried it myself.