Lots of smarter people than me have written about what Javascript is and how it compares to other languages.
Some people say that it's a radically different language from others, and I guess that's true.
But as a beginners language, it's not at all bad, in my opinion.
Most programming languages start from the idea that when you interact with a program, it's by 'running' it.
A program, then, is thought of as a series of statements that are 'executed' one after another by the interpreter.
Alternatively the program is read by a compiler and turned into a machine code file which can then be run by the operating system.
A typical javascript program, however, loads alongside a web page. It might do some things right away upon loading, but it might also wait until the user interacts with the web page before running.
In this sense, most javascript programs follow a very different paradigm to those written in other languages but that doesn't mean that you have to do it that way.
If all we put in our javascript program is a series of statements, they will be executed one by one when the program runs. To get it to run we can embed it in a webpage and (re)load the page in a browser, or we can run it using node.js.
Here are the bits of javascript that you can learn and might need just writing simple 'calculations'.