Big Data Analytics isn't hard but a very wide subject to master. It has got various tools and techniques that you must master to gain proficiency in the subject. There are a variety of skills that you must acquire to bag better opportunities in the field. If you aim for a career in this field, I recommend you check out this Big Data Analytics Certification from E & ICT Academy from IIT Guwahati through Intellipaat.
I will also share a video of a learner who completed the course and has appreciated us for having excellent trainers and apt course material.