If you distrust all third-party tools, you can attempt a manual recovery. This works primarily for older software (pre-2020) that stores keys in plain text.
If you are looking for a free license key for the Password-Find password-find license key free
If manual methods don't work, these utilities scan your system and registry to retrieve keys for Windows, Microsoft Office, and other third-party software: If you distrust all third-party tools, you can
If you want, I can:
Is this to software to a new computer or just to repair an existing one? If you distrust all third-party tools