Jailbreaking an iPad Air (1st Gen) on iOS 12.5.7 can be accomplished using Chimera, Freya, or Checkra1n, with options for both computer-free and computer-based installations. Key methods involve installing the Chimera app via Safari, using Freya on A7-A11 devices, or applying the stable Checkra1n hardware-based exploit. For a visual guide on the process, watch this YouTube video
Preparation: Download the Chimera IPA file and a sideloading tool like Sideloadly or Cydia Impactor on your PC or Mac. How To Jailbreak Ipad Air Ios 12.5.7-
Preparation
Restoring Your iPad (Optional)