clang --version
clang version 10.0.0-4ubuntu1
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
İnstall Clion or Qt Creator.
Open a BP Project, then go to Edit → Editor Settings, and finally “Source Code”. There’s a dropdown to select your editor. CLion or Qt Creator should be detected and compatible. if will not just reinstall UE4