The From dropdown selects the start of the range of letters you wish to practice
The To dropdown selects the end of the range of the letters you want to practice
The Dropdown on the top left selects whether you want to Hiragana or Katakana letters to be displayed
Click start, when you do that, a random Kana letter, based on your specifications will be displayed on the
left side
You're supposed to write its Romaji form in the text box labelled "Answer"
Once you do, you click the Check button or press Enter, when you do this, the correct answer will be displayed
on the right side, colored red if your answer was incorrect and green if it was correct, and,
the button will change to "Next"
To get the next question, click the button Next or simply press Enter
To change any of the options after starting, preferably click Stop first