Animations in C++ work different than in Python.
To load an animation, you need to load it as separate model and bind it to the model. The auto_bind function gives you an AnimControlCollection, where you can extract your AnimControls from. You can use these to control your animation.
For example, if you want fine-control of the animation in the Hello World example:
#include "auto_bind.h"
#include "animControlCollection.h"
//...
//load our panda
NodePath pandaActor = window->load_model(framework.get_models(),"panda-model");
pandaActor.set_scale(0.005,0.005,0.005);
pandaActor.reparent_to(window->get_render());
//load the walk animation
window->load_model(pandaActor,"panda-walk4");
AnimControlCollection panda_anims;
auto_bind(pandaActor.node(), panda_anims, 0);
//now you can do with _panda_anims whatever you want, e.g.:
panda_anims.loop("panda_walk_character",true);
//where panda_walk_character is the name of the animation.
I’m currently in the process of creating a tutorial that will explain these things some more.
Hope this helps.