This course introduces key concepts of 5G New Radio (NR) mobile communications and emphasizes security research for next-generation (6G) systems. It highlights practical, link-level wireless communication principles essential to 5G NR and integrates hands-on operations. As a graduate-level offering, the course also explores current research trends in 6G development. Designed to provide a foundational understanding of 5G NR, the course aims to narrow the gap between academic knowledge and industry applications. Students will acquire practical knowledge and investigate relevant security and privacy issues within these advanced communication technologies.