Difference between various frameworks and languages for backend

I am in college right now, and I am a machine learning enthusiast. I wanted to learn backend so that I can deploy my machine learning algorithms in hackathons and for the future as well. While I was browsing through the internet regarding backend, there were various terms that I came across. And since I am new to the backend, it all seems very confusing to me. So I want a simple layman's explanation and suggestions for how to proceed with learning backend and applying it to my ML models and also for the future (job). These are some of the languages/frameworks/technologies that I came across. Please help me understand their actual use. And which of these do I need to learn and which are actually popular?
1. Java Servlet
2. JDBC/ODBC
3. JSP
4. Django/Flask/Nodejs
6. MongoDB/SQL
7. PHP
8. React/Angular
9. Kubernetes
10. ASP.NET
11. IBM Watson

I am actually very confused about which of these has what functionalities and why is it used for backend. I want to get a clear understanding of each of these as I feel if I'll do one of these then maybe that won't be sufficient for the backend development. Thank you.