Start with the basics. I assume that you are customizing a Windows installation by the use of an answer file (unattend.xml). The error message tells you that offlineServicing step is borked. Remove that step and test. Tell us exactly what you are doing, and avoid posting confidential information such as pre-configured passwords.
Either do that or open the xml file in Notepad and remove that part. Copy/paste the xml content here in [. code] [./code] tags (remove . inside brackets before posting)
Open the unattend.xml file in a text editor; Look for the section that starts with <settings pass="offlineServicing"> and ends with </settings> Remove this entire section from the file, or modify it as needed to resolve the issue; Save the changes to the unattend.xml file; Test your Windows installation again to see if the error is resolved. Using homebrew ISOs from non-official sources is unsupported and "at your own risk". For a stable and supported installation, I would recommend using official Microsoft sources for your installation media. This will ensure that you have a genuine and reliable installation.
Delete or rename the unattend.xml file to an unrelated name, so it will be ignored. Start the process from scratch. The installation medium may be corrupt.