Open a Mesh in ParaView (SimScale, OpenFOAM)

Thanks and please let me ask you some basic questions soince I am new with meshing and Geo file and I have a ready .msh file and the original .geo file that is shown in the attached picture.

My aim is to midify the .msh file which is required for MOOSE simulation and so I want to edit .geo first ==> generete the .msh ==> employee it in my simulation. Coudl you pleae describe easy tool to handle the procedures.