After May 2017, Microsoft stopped patches. WannaCry, NotPetya, and every major exploit since then can infect a 1507 machine within minutes of internet exposure.
Yes. Running the setup from a Windows 10 22H2 ISO while keeping files and apps works, provided your hardware meets the newer requirements. windows 10 1507 iso download
Microsoft no longer offers 1507 via official download tools (Media Creation Tool only gives latest version). However, official ISOs are archived by Microsoft on MSDN / Volume Licensing (paid) and via unsupported but authentic channels: After May 2017, Microsoft stopped patches