No, just an awning or canopy will not protect plants from a hard freeze. The problem with a hard freeze is that moisture that accumulates on the leaves of the plant from the dew or rainfall becomes frozen and damages the plants. A blanket is good for a hard freeze because it keeps the dew off of the plant and protects the plant from the cold. The awning will help to minimize damage, but the plants can still freeze. It is always best to cover them or bring them indoors.
Yes, an awning and a canopy will protect plants from a hard freeze. Also, a layer of mulch is usually recommended for plants during winter and after the first freeze. Mulches help by reducing water loss from the soil and hence help in transpiration, and also reduce the heaving of the soil as the soil freezes and thaws during cold months.