Following the same logic as the previous two libraries, you can use the torch.nn.EmbeddingBag class to inject the pretrained embeddings. There is a small drawback though. Keras and TensorFlow make the assumption that your tensors are actually implemented as NumPy arrays, while in the case of PyTorch, that's not the case. PyTorch implements the torch tensor. Generally, this is not an issue, but this means that you will need to write your own text conversion and tokenizing pipelines. To circumvent all this rewriting and reinvention of the wheel, you can use the torchtext library.
PyTorch
The torchtext library
The torchtext is an excellent library that takes care of most of the preprocessing steps that you need to build...