Hi Heng,
For Modelio2.x, you can directly find it under your $installPath/modelio2.x/mdk folder.
For Modelio3.0, you can directly find it under your $installPath/modelio3/plugins folder.
But if you want to develop a Modelio module, it would be easier to use the Modelio Maven template, more informations are available here (for Modelio2.x) or here (for Modelio3).
Hoping it helps,
EBR
For Modelio2.x, you can directly find it under your $installPath/modelio2.x/mdk folder.
For Modelio3.0, you can directly find it under your $installPath/modelio3/plugins folder.
But if you want to develop a Modelio module, it would be easier to use the Modelio Maven template, more informations are available here (for Modelio2.x) or here (for Modelio3).
Hoping it helps,
EBR