You should consider using an Integrated Development Environment (IDE) such as Visual Studio Community. It free, contains editor, compiler and debugger.. Yes, it's a bit of a learning curve, but it gives you all the tools you need for writing, compiling and debugging any project you want to write. Keep in mind that as you learn C++, you're going to rapidly move past the simple single file programs such as "Hello world".
I use Visual Studio as an IDE, but also I like the Code::Blocks embedded editor. Some prefer Eclipse - some another one. In conclusion, your IDE is about making choice - a simple question of personnal preference . No specific rules ++
Notepad++ is a better editor than most. With syntax coloring, macros, line numbers, block copy and paste, it supports everything you will need on the editing side. I use it because visual studio removed their macro support among other reasons.
You may still want an IDE, but you can't ask for a better pure editor.
If you want a code text editor - as opposed to an IDE - then have a look at Visual Studio Code (as opposed to VS the IDE). This is x-platform (Windows, Linux, Mac).
Your choice of editor is ultimately a personal preference. There is no clear "best".
Notepad++ is based on Scintilla, a library component which actually handles the text-editing.
This is the same backend as used in Code::Blocks, CodeLite, Geany, and many others.