If you see a file labeled "Windows 7 Ultimate 64 Bit Highly Compressed 10mb.exe" on a torrent site or file-sharing forum, you are not downloading Windows 7. You are downloading one of three things:
Sometimes the 10MB file is not the OS itself but a small installer or torrent file. Once you run it, it connects to a server or peer network to download the actual 3-4 GB of Windows 7. In this case, the "10MB" is misleading marketing. Windows 7 Ultimate 64 Bit Highly Compressed 10mb
To understand why you will never find a legitimate Windows 7 Ultimate 64 Bit Highly Compressed 10mb file, you need to understand how compression works and how large Windows 7 actually is. If you see a file labeled "Windows 7
Windows 10 LTSC (Long-Term Servicing Channel) removes the Microsoft Store, Cortana, Edge browser, and other bloatware. It can run on 2GB of RAM and installs in about 8GB of space. In this case, the "10MB" is misleading marketing