I have installed the Pycharm Community edition and installed the behave 1.2.5 with the following command.
pip install behave
AFAIK "BDD support is available only in the PyCharm Professional Edition." Of course, nothing prevents you from creating a file with the .feature extension but you are not going to see options to run your scenarios. You can get some syntax highlighting using the Gherkin plugin and that is as much as you get in the community edition.