Use a tool like AltStore or Sideloadly to install the file.
Google "iGameGod IPA free" and you will find 50 sketchy forums. Most of these are dangerous. Here is what to watch for: igamegod ipa file free
The official tool is developed and maintained by iOSGods, a well-known community for iOS game modifications. The Danger of Fake "Free iGameGod" Sites Use a tool like AltStore or Sideloadly to install the file