Marek Kowalski completed a five-course specialization in Data Engineering on Google Cloud Platform from Coursera. The specialization covered topics like big data fundamentals, machine learning, and building streaming systems on Google Cloud. Through video lectures, quizzes, and hands-on labs, learners analyzed data with BigQuery and Cloud Dataflow and productionized machine learning models with Tensorflow on Google Cloud. The specialization provided a robust hands-on experience focused primarily on labs.