To explore the different domains, first you have to get familiarised with the courses that you will be studying in your undergraduate program.
You cannot deep dive before you learn to float. So take up your UG subjects seriously. Slowly you will figure out your favourite subjects. Make sure you get your Mathematics fundamentals right. That will give you a strong foundation to understand all the branches of computer science you have mentioned in the question.
You have lots of resources available online. Google will be your saviour.
Hi, there are different specialisations available in computer science like Artificial Intelligence, Data Science, Data Analytics, Cyber Security, Cloud Computing, etc. And it depends on your interest which one to choose. You should know the details, career opportunities and scope in all these fields before choosing so that you could make an informed decision. I myself searched for computer science courses and came across Shoolini University, which is the No.2 Engineering University in India. They have all the specialisations to choose from. Must visit their website to get more details.