TensorFlow GPU is the short form for the Graphical Processing Unit which breaks the complex tasks into smaller separate tasks and solves them at once. GPU is good for parallel processing and helps to train and run deep neural networks that require faster computations.
If you want to learn TensorFlow, you can register for this Artificial Intelligence course by Intellipaat.
Learn more about Tensorflow and Keras on Tensorflow vs Keras.
You can watch this video on TensorFlow in 10 minutes to learn TensorFlow: