"Compliant" means that the compiler correctly implements C++11.
If you tell us which compiler you have (remember, Visual Studio is not a compiler, and neither is Dev-C++, Code::Blocks, Eclipse or Qt Creator) we can tell you how to tell it to use C++11.
Yes, that's not a compiler. I did say "remember, Visual Studio is not a compiler, and neither is Dev-C++, Code::Blocks...". Never mind. I am going to guess that you are using the GNU G++ compiler.
Run in terminal gcc --version
(If the compiler binary has other name than "gcc" or is not directly on the path, then figure out the proper name first.)
There is no "lol" in the equation. You either know the tools that you use, find out what they are and how they are used, or simply don't.
If you do use GCC or Clang compilers, then their default language dialect is not C++11, even though they might support C++11 (and C++14, and putative C++17).
However, they both should have command-line option -std=ver, where the ver is the language dialect that you need.
You must check from the documentation of the version of the compiler that you do have, what are valid values for ver.
You must check from the documentation of the version of IDE that you have, how to pass that option to the compiler, when the IDE executes the compiler.