Languages don’t get you more money, problem-solving capabilities do.
There is a subtle, but an important difference between a Programmer and a Software Engineer. While a Programmer knows how to write code, a Software Engineer can solve a technology problem. A Software Engineer understands a particular situation and is able to craft a technology-backed solution for it. One of the aspects of this solution is to build a Software for the same and that’s the only part that requires Programming.
That’s why skilled Software Engineers are paid higher. They know a lot more than just writing code in 3 different languages.
You may learn 10 different programming languages. But, can you really build something that solves a need? Can you come up with a creative technology-backed solution to a problem in a specific situation? Or, do you just know the syntax of C/C++/Java/Python/whatever? You can make money if you have problem-solving skills. You won’t make money if you are just a Coder/Programmer.
My suggestion - pick up a single language. Ideally, if you are still in college/university, start with C++. It will help you build solid foundations in not only Programming but also in the general Computer Science domain. If, however, you are out of college and are seeking a career shift in the Software Engineering domain, I’d suggest that you start with Python. You can easily pick it up and the rewards are good - you can quickly get a job since Python is high in demand in the market.
Whatever you start with, aim to become a Software Engineer and not just a Coder/Programmer. The bigger the problems you’re able to solve, the more value do you create for others and accordingly, you’d be paid a lot more.