This is mentioned for completeness. MSDN (Microsoft Developer Network) and TechNet subscribers historically had access to direct ISO downloads. However, this requires an expensive paid subscription and is not a realistic option for most home users.
Since Microsoft has removed the direct downloads, finding a safe and legitimate ISO requires extra caution. Downloading from random, unverified sites can expose you to malware and modified, unsafe copies of the operating system. Below are the most reliable and recommended sources.
: Given that Windows 7 is no longer supported, consider using a modern operating system like Windows 10 or Linux distributions for better security.