Hi, great story!
Once upon a time, there was a little girl who was afraid of darkness. Her name was Marine and she lived with her parents
"Don't worry, you're going to sleep well", her mother said at the end of story.
==> In English, you don't have to reverse the subject and the verb after a quotation.
She drew the curtain ==> keep the past form and not the present [to draw / drew /drawn].
A strange noise ==> i think you wanted to use the adjective "strange" (=weird)
Frightened, she crept under the covers, she thought and a plan came to her ==> being is useless
Elle prit son courage à deux mains = she mustered / plucked up courage