@Avinash I started out with core Spring, because I wanted to understand the things that actually happen behind the scenes “automagically” when you use Spring Boot. Learning these concepts helped me understand the basic building blocks that Spring (and Spring Boot) is based on - container, application context, DI, IoC, etc.
Then I learnt Spring MVC (with just Spring, not spring boot yet), as that is what you would use for almost every web app that utilizes Spring. Here you’d learn concepts like the Front Controller (Dispatcher Servlet), how M-V-C is organized, etc.
Then I took up Spring Boot to build a Spring MVC app, and this is where the power of Boot really shines, no need of configuring the servlet mappings yourself, for instance, is just one major benefit.
I had some experience with JDBC, and Hibernate, so then I took up Spring Data JPA, and how it makes things really easy over using just plain Hibernate (which in itself is a big step-up over just JDBC).
Up next is Spring Security for authentication, then Spring Cloud, and more interesting projects from the spring.io projects.
Hope this helps!