.I have set password and forget it

Bios passwords must have specific information.

Windows passwords will require reinstall.

https://www.dell.com/support/article/us/en/04/sln142655/dell-system-prompts-for-a-hard-drive-hdd-or-bios-password?lang=en

Contact Dell for Password release code

On contacting Dell Technical Support you will be asked to confirm the below for security reasons:

• Ownership of the computer.
• Whether you are authorized to clear the password on the system.
• Contact Information.

Please have the full error message along with your system Service Tag information as this is required to create the release code.