You really do need all of the following:
Ski goggles (possibly sunglasses if the weather is good)
If you're going somewhere cold (check weather) make sure you have plenty of warm clothes & a scarf/balaclava or something similar. As a beginner you spend more time standing around than a more advanced skier and if you're cold you won't enjoy it.
All these things are frighteningly expensive and you'll really regret it if you miss out on any of them.
Good news - you can hire most of them. You will definitely hire boots, skis and poles (the most expensive parts) wherever you are skiing.
If you can, find friends who ski and borrow goggles, hat, gloves, socks etc.
A nice ski jacket is quite expensive (in UK doing well to spend less than $120 and can easily spend over $500) but is useful whenever it gets cold - not just for skiing.
Ski trousers unfortunately also cost but you do need them. Some places will let you hire ski clothes for a week.
Have a great time!