It is always recommended to call ahead and make a booking, often Wahroonga Optometrists can be booked out well in advance.
Yes, contact lenses are a very common item from Optometrists. They will be able to recommend the type of lens best suited to your eyes.
Prescription glasses are designed to correct your vision so you can see clearly. They do this by using a lenes that changes the way the light hits your eye.
To become an optometrist you have to study optometry at university either by completing an undergraduate or postgraduate course in optometry.