As my opinion you have to focus on only one language but day by day things are changing so you can't stay on only one language. For example suppose once a time java was popular but now a days python is popular or artificial intelligence is popular.
Insted of learning many languages try to learn basic concepts which are common in all languages such as variable initialization, operators, functions etc then try to learn OOP concepts such as inheritance, polymorphism etc because in all languages almost every thing is common but the way of doing it is different soo if you know these concepts, you can easily grab different language.
hope it helps .
Master in one programming language will help you to learn other programming language easily
So learn one programming language and master it. after learn any other programming language depend on your needs
Try to avoid learning many languages. There are libraries and frameworks for each language. Some languages will not be on the scene after a few years, like Ruby or R, and you may not even use them for real work. Mastering in complex languages like java or c ++ takes years.
I think it's a waste of precious time to commit to learning all programming languages on this platform. Learn only what you need on as needs basis. Your learning curve is acute and exponentially heightened when you're learning a language because you have to build with it, as against learning for chewing gum knowledge.
As long as you understand all the basic concepts like OOP, etc. you can export that knowledge across languages.
Why learn Ruby if you ain't coding Ruby? Better be deep than broad.
My personal advice is to learn the basics of all the languages you will use but pick one you like and specialize in that. This will allow you to know other languages in case you need them but also still be able to use a language you like more often and easily
It is fun and nice to learn multiple languages but can you do it properly? Learning the basics is easy, but to master one language you need year(s). So do you have time to master multiple languages? And if you do it, does it help you?
Best for me is mastering one and then for fun or pleasure or i dont know, go to another. But first learn one well.