Programming

Python is the older of the two languages. In programming language evolution, it is common to maintain backward compatibility indefinitely. This is not the case with Python. Python versions are largely compatible but have enough functionality- and syntax-breaking differences that they can be treated as different languages. Python is adapted because of Simplicity, Open source, object-oriented and General purpose language. It is an interpreted language available on many platforms, making it a portable option for general development.
Java on the other hand
Its attraction and value is its portability and relative efficiency. Java is a compiled language, unlike C/C+. Its execution model is more machine-centered than purely interpreted languages. Java is more than just a language and libraries. It is also a virtual machine and, therefore, an ecosystem. The Java Virtual Machine (JVM) is an idealized and portable platform for running Java code. Rather than worrying about hardware specifics and having to port code to new platforms, the promise of Java has been written once, run anywhere. That is so that as long as a JVM is present, anything compiled into its bytecode can run and interact easily with anything else written for the JVM.

Perl is a programming language developed by Larry Wall, specially designed for text processing. It stands for Practical Extraction and Report Language. It runs on a variety of platforms, such as Windows, Mac OS, and the various versions of UNIX. This tutorial provides a complete understanding of Perl. Prior knowledge of C/C++ or UNIX shell programming is preferred for Perl programming. Courses for Perl developers may include computer systems, algorithms, data structures, machine architecture, software engineering, linear algebra, and discrete math. Because Perl is a dynamic programming language that differs fundamentally from languages such as C/C++ and Java. There are many online courses available for Perl on Udemy, Lynda, Coursera etc. Check the below link for institutes offering Perl courses - https://www.shiksha.com/it-software/colleges/perl-colleges-india

It is very straightforward, but not easy. You should learn in an effective general way like you would study any other subject.
Pick study materials of an appropriate level, do not rush things. For example, pick a book on programming language like Python for beginners, take a MOOC course and practice a lot as you learn new material.
Read a few books on different topics like programming languages, networks, web, OS, databases, algorithms and data structures, GIT. This will set a good base for you.
After you read a few books and practice all that you will know yourself how to continue, what to learn and what's the most efficient way for you.
It's really straightforward, but takes time to become good at it.
Keep learning new languages like every year or so, and master at least one.