How to make a project compatible for an older version of Unreal Engine.

I have uninstalled and reinstalled version 5.7.4 many times. I am a student and do not have access to run it as an administrator. Whenever I tried to launch versions 5.7.4, it states that the prerequisites have failed to install. Older versions are working fine, however, my project that I am trying to work on cannot be opened in the older versions, only version 5.7.4 of Unreal Engine.

That said, my campus IT is not available, so is there a way I can make my project that I used on the 5.7.4 version become compatible to work on an older version that does work such as version 5.6.1?

No. Engines are not forward compatible. Additionally, projects can be upgraded only, not downgraded.

Hey there @Eres5515! Welcome to the community! As mentioned, there is no native backporting capabilities. For the most part it’s often better to take the constituent parts and rebuilding. However there are some community utilities for backporting assets mentioned in this thread, but they are far from reliable.