Extensive Reading Central is a site where you can read and listen to a variety of stories and dialogues, then take quizzes about the content, take speed-reading tests, play games to improve your vocabulary, and more. You do have to sign up, but it’s free to use. When you sign up as a student, you’ll be asked to choose your level for both reading and listening, and there are short texts for you to read/listen to so you can judge which level you’re most comfortable with.
Here’s one example from the listening section:
As you read, you can check definitions of unfamiliar words or highlight words you want to remember by right-clicking. You can save the word to your “Vocabulary Room” and take quizzes and play games later.