Including the Header File

Set the directory to the appropriate place where the header file is to be saved

SetDirectory["D:\chris_lum_D\mathematica\module_tutorial"];

Read in the header file (similar to a #include in C or C++)

<< moduleH.nbd

Now test that all the functions are defined

MyFunSimple[x, y]

MyFunComplex[π, π]

AnotherMyFunComplex[2]