Microsoft ended official support for Windows 7 in 2020. Using an outdated, unofficial version means you won't receive security updates, leaving your PC wide open to remote hacking.
If you have a legitimate ISO and wish to install it, your PC must meet these minimum specs: Microsoft Learn Windows 7 32 bit minimum spec - Microsoft Q&A Windows 7 Ultimate 64 Bit Highly Compressed -9.28 Mb
Even the most stripped-down, unofficial "SuperLite" versions rarely go below 900 MB to 1 GB . Windows 7 Ultimate 64-Bit Minimum System Requirements Microsoft ended official support for Windows 7 in 2020