Because it no longer receives monthly cumulative updates or security patches, using 1507 as your primary, daily-driver operating system connected to the internet exposes you to unpatched vulnerabilities. However, if you are running it in an isolated virtual machine (VM) or an offline air-gapped environment, it remains perfectly safe to use.
Before installing Windows 10 Version 1507, you must understand the security and usability trade-offs: windows 10 1507 iso download
What (CPU/GPU) are in your target computer? Because it no longer receives monthly cumulative updates
