Can I use ANSI C instead of C++

Please forgive me if this has already been asked (searching for “c” returns a lot of “C++” hits as you can imagine).

I’m curious if the c language can be used for programming UE4 on Linux (Debian) or if it has to be c++ (no, c++ is not just an extension of c).

No, as UE4 itself and its APIs are written in C++. Note that by programing in UE4 you technically extending engine itself and your code is part of the engine, you just adding your module to already existing once. So you forced to use C++ at lowest level of UE4

Ok, thanks for the info.