Coding requires a tool in which to write your code. The tool you use can make a big difference in how productive you are. Some people find that using Interactive Development Environments (IDE) like PyCharm to be the most productive. Others might have a preference to use simpler text editors. IDEs like PyCharm will help improve your productivity through features like auto-complete, syntax highlighting, and error checking. There are many IDEs similar to PyCharm, including Sublime Text, TextMate, and more (here's a good list of more options). PyCharm happens to be the one that I find most productive and use personally.
PyCharm has both a free and paid version. You can go to PyCharm's site to learn more. If you choose to use PyCharm as your IDE, it can be easily installed from the same website.
You can use any IDE or text editor in this course. Just be aware that screenshots may show sample code in the PyCharm environment. The good news is that the code will still be the same no matter what IDE you use.