#On your own
Design and create a MeshManager for OBJ files. Utilize the OBJ loader created in the last section for this. You will need an inner helper class just like the TextureManager did, instead of tracking an OpenGL handle you will be tracking OBJ objects.
You don't need to include any of the loading code in your manager class, because the OBJLoader classes constructor already takes care of that. Essentially, only make a new instance of OBJLoader when something needs to be loaded.
If you want you can write a class skeleton and get my feedback, or if you feel comftrable you can just build the whole thing in one go.