Provided that cucumber support is enabled you should be able to run the test from .feature file’s context menu:
Also in Run/Debug configurations window -> Cucumber java -> what should be the main class?
The class is taken from the jar archive attached when enabling Cucumber support in project. By default, the main class name is cucumber.cli.Main
:
Do not forget to specify the package where your step definitions are stored in the Glue filed of the Cucumber Run/Debug Configuration.