How to start using JavaScript with Python

I am fairly new to programming. I am well versed in Python. I can write a fairly complex Python script. But now what? How do I convert the code to JavaScript? The biggest part of the transition I am having trouble with is what do programs are used where. In python, I can use pip to install libraries, and I use PyCharm to write programs. In JavaScript, I have learned you can use npm too install libraries (for all intents and purposes in the same way as pip) but where do I write the code? Do I write it in a browser? If so, how do I start what I wrote? In PyCharm, I can simply click the run button. If you can give me the basics of what needs to be done too convert from python to JavaScript, and what program I need to be using to do so, that would help me a lot! Thanks.