Which platform? On Linux it's /opt/intel/bin (softlink to latest installed version) On Windows it is in C:\Program Files (x86)\IntelSWTools\compilers_and_libraries_2020\windows\bin\intel64 or \intel64_ia32 (for the 32-bit cross-compiler). I think Mac is similar to Linux.
But you should not care - instead you should be establishing the compiler environment using the supplied script (ifortvars.sh on Linux, ifortvars.bat on Windows - shortcut in the Start menu.)
Steve (aka "Doctor Fortran") - https://stevelionel.com/drfortran