JetBrains Idea : new projects, not resolving or compiling classes...
One of it's reason : because your folder has a non-latin character in it's name.
try removing all non-latin characters.
https://intellij-support.jetbrains.com/hc/en-us/community/posts/360009445579-Error-Clion-2020-2-The-C-compiler-is-not-able-to-compile-a-simple-test-program