If you are just trying to move values between Python and C++, the API in this comment 33 is now the blessed way to do that. But to answer your question, for a model like
import torch

class Model(torch.nn.Module):

    def __init__(self):
        super().__init__()
        self.w1 = torch.nn.Parameter(torch.ones(2, 2))
        self.w2 = torch.nn.Parameter(torch.ones(2, 2))

    def forward(self):
        return self.w1 + self.w2

m = torch.jit.script(Model())
torch.jit.save(m, 'model.pt')

You can iterate over the parameters like:
#include <torch/script.h>

int main() {
  auto m = torch::jit::load("model.pt");
  for (torch::jit::script::Named<at::Tensor> p :
       m.named_parameters(/*recurse=*/true)) {
    std::cout << p.name << ": " << p.value << "\n";
  }
  return 0;
}