Door
Hinged Door
noun
Like the kanji, this means door.
You've already learned 戸 (door), but 扉 is a bit different. While 戸 can refer to any kind of door (though often sliding ones), 扉 more specifically refers to a hinged door, including things like gates or panels that open on hinges.
Because 扉 evokes the image of a door that swings open, it's also sometimes used metaphorically. For example, a book's front page can be called a 扉, and you'll see expressions like 心の扉 (the door to one's heart) too.
This word is made up of a single kanji, so you know it'll probably use the kun'yomi reading. Fortunately, that's the とびら reading you learned with the kanji!
おい、ふざけている場合か！扉を開けろ！
Hey, this isn't funny! Open the door!