Running third-part executables in the main executable

[IdeaD]

I am new to NSIS. I have differents components to put in an executable. For example: Python, R, etc. and my main executable (MyApp.exe).With this code, it just copies the Python.exe and R.exe to the installation path and not installing them:

Section -SETTINGS
SetOutPath $INSTDIR
SectionEnd

Section "Python" SEC01
File "python-275.msi"
ExecWait '"$INSTDIR\python-275.msi" /passive'
SectionEnd

Section "MyApp" SEC05
File MyApp.exe
SectionEnd

Thank you for your kind help.