Meteor vs Phoenix Framework vs Spring

Is learning Spring and Spring Boot for web apps back-end development is still relevant in 2021? Feel free to share your views with comparison to Django/Node.js/ ExpressJS or other frameworks.

Please share some good beginner resources to start learning about spring/spring boot framework to build the web apps.

I am provided with the opportunity to learn one of these technologies during my training. I have prior experience with Spring and found it tough and still haven't figured out when to use what annotations among the thousands of annotations provided. On the other hand, I am very proficient in Java data structures and algorithms (custom comparators, etc.)

I have used Node.js and found it interesting, but I am wondering If I am taking the risk of choosing a framework that has a comparatively lesser scope in the future. One advantage I see with the node.js is the number of tutorials available and the ease with which I can code.

Please recommend which path to take. Is Spring learnable, or should I spend my energy on learning Node.js instead?

I am a graduate student working as a software engineer in a company. For my personal development, I want to learn web development. I have some experience in Springboot while I was in university. So I want to continue with spring-boot, but I heard about Django. I'm reaching out to the experts here to help me choose a future proof framework. Django or Spring Boot?

Thanks in Advance