You really should open a window at least slightly while getting the fireplace going as having the window crack open will help get the chimney drafting the smoke up the chimney instead it back drafting into your house.
If your fireplace is an open fireplace and not a fireplace insert you should extinguish the fire in the fireplace before leaving the house or going to bed.
Fireplace fires should not be left burning unattended but a wood stove or fireplace insert can be burned at night or unattended as long as it was properly installed.