Second, you'll need to enable launching using MPI for your particular project.  In the Project Options window, go to the "Launch" category.  You'll need to click the options "Launch Using Message Passing Interface."

Finally, you need to link the MPICH library to your executable.  The MPICH library, on Debian/Ubuntu, can be linked by adding the following flag to the Linker box under Compiler Flags in Project Options:

-lmpich

It sounds like you should have most everything working already on Linux, though, if it all works through the command line.  I should note that Simply Fortran's debugger will not work properly with MPICH controlling your executable.  It would be best to debug the program as a single-thread/single-image implementation prior to moving to MPI.

I am currently running my code with OpenMP on SF (Build 3.2 , 2981). I want to switch the code to MPI and want to try out few 'Hello World' runs using MPI.

(PS:I have gfortran and MPICH already installed and the hello world runs without errors on the terminal)

As I went through the forum, there is a package which is meant to run on windows. Any pointers on how I can run SF with MPI?

or is it not possible ?