How to make a mesh editable for unity3D

well i have a 3D model of the human digestive system I found it in the internet, this model is :

• a .obj file
• if a fixed model (not dynamic)

here is screenshot of the model :

so what I want is to make this model editable on the game like for example the user of the game can cut the intestine and suture it (so in other way making a surgery)

I'm not sure if it is possible or i should create a new model from scratch to do that

Note :

I'm working with unity3D for creating the game and I'm trying to adapte the model with what I want using blender and cinema 4D so whatever the tool needed to do it i will use it

You should first go through these two pages to understand how meshes work and how you can manipulate them in Unity.

Using the Mesh Class

Mesh

Unity isn't a mesh editor, it's an engine. You can write your own scripts to add the functionalities you need, or also there are some pre-made assets that do some mesh editing available in the Asset Store.

The best approach is to remodel all in small fragments so you can easily cut the pieces you want.