If you simply prefer the Windows 7 interface on modern hardware, consider using with a third-party skin or "Classic Shell" software. The performance and security improvements are non-negotiable.
Today, searching for a "Windows 7 Professional ISO" is an exercise in digital archaeology. While Microsoft has officially ended support, the ISO (the exact digital image of the installation disc) remains a vital tool for specific industries, legacy hardware, and virtualization enthusiasts. iso windows 7 professional
If you didn't pay for it via a legitimate channel, or if the ISO asks you to disable your antivirus "to run a crack," you are not getting Windows 7—you are getting malware. Proceed with caution, or better yet, virtualize it safely. If you simply prefer the Windows 7 interface