Are you trying to install a specific like Unc0ver, or just a custom IPA file for an app? Knowing that can help me point you to the best tool for the job.
The assert code 200 error in Cydia Impactor is a . No local patch can resolve this because the authentication protocol has fundamentally changed. Cydia Impactor should be considered end-of-life (EOL) for the purpose of sideloading with a free Apple ID. Users requiring sideloading functionality must migrate to modern alternatives such as AltStore or Sideloadly. assert code 200 cydia impactor