Is there proper folder location?

[KJH199701]

At first, Thanx for share the project, sorry for long text, i submit my some errors.
i did all prerequirements(1~4) , but there are some errors...kinda

// for run wmake, maybe this one is why i ask this question
// my folder root OpenFOAM/username/run/

Making dependency list for source file MTO_Fluid.C
could not open file mpi.h for source file MTO_Fluid.C due to No such file or directory
Making dependency list for source file MMA.C
could not open file MMA.h for source file MMA/MMA.C due to No such file or directory
Making dependency list for source file adjointOutletVelocityPowerFvPatchVectorField.C
could not open file adjointOutletVelocityPowerFvPatchVectorField.H for source file adjointOutletVelocityPower/adjointOutletVelocityPowerFvPatchVectorField.C due to No such file or directory
Making dependency list for source file adjointOutletPressurePowerFvPatchScalarField.C
could not open file adjointOutletPressurePowerFvPatchScalarField.H for source file adjointOutletPressurePower/adjointOutletPressurePowerFvPatchScalarField.C due to No such file or directory
mpic++ -std=c++11 -m64 -Dlinux64 -DWM_ARCH_OPTION=64 -DWM_DP -DWM_LABEL_SIZE=32 -Wall -Wextra -Wold-style-cast -Wnon-virtual-dtor -Wno-unused-parameter -Wno-invalid-offsetof -Wno-attributes -O3 -DNoRepository -ftemplate-depth-100 -I/opt/openfoam6/src/TurbulenceModels/turbulenceModels/lnInclude -I/opt/openfoam6/src/TurbulenceModels/incompressible/lnInclude -I/opt/openfoam6/src/TurbulenceModels/compressible/lnInclude -I/opt/openfoam6/src/transportModels -I/opt/openfoam6/src/transportModels/incompressible/singlePhaseTransportModel -I/opt/openfoam6/src/finiteVolume/lnInclude -I/opt/openfoam6/src/meshTools/lnInclude -IlnInclude -I. -I/opt/openfoam6/src/OpenFOAM/lnInclude -I/opt/openfoam6/src/OSspecific/POSIX/lnInclude -fPIC -c adjointOutletPressurePower/adjointOutletPressurePowerFvPatchScalarField.C -o Make/linux64GccDPInt32Opt/adjointOutletPressurePower/adjointOutletPressurePowerFvPatchScalarField.o
...(omission)

// All running code wmake
$ mpirun –n 20 MTO_ThermalFluid –parallel

mpirun was unable to find the specified executable file, and therefore
did not launch the job. This error was first reported for process
rank 0; it may have occurred for other processes as well.

NOTE: A common cause for this error is misspelling a mpirun command
line parameter option (remember that mpirun interprets the first
unrecognized command line token as the executable).

Node: username-VirtualBox
Executable: –n

2 total processes failed to start

[KJH199701]

IDK why above error didn't show again, but there is another one.
it didn't work when use
mpirun –n 20 MTO_ThermalFluid –parallel
with some error,

but work with
mpirun –np 2 MTO_ThermalFluid –parallel

I don't know well, but i think maybe "20" invoke error. can you give some opinions for solve this?