Deep Learning specialization is actually a very good next step, then you can dive deeper into tensorflow. You can take the tensorflow professional developer certificate which is also provided by deeplearning.ai. then you can practice some projects on kaggle. at this point it is very important to learn pytorch as it is widely used. If you would like to work on NLP or GAN projects, then take their specializations, if not don’t worry, you don’t have to learn them to be a machine learning engineer.