Hi Celeste, I am not a skier, but we own a small condo at a ski resort in the Tahoe area. Our daughter and daughter in law ski, and our son in law is a snow boarder. Of our 5 grandkids we only have one serious skier.
First of all, it is not cheap, lift tickets are expensive, but some resorts are more expensive than others. A little research would probably help. I don't know which area in which you are interested. Ski equipment is best rented for the first time or two. Sometimes there are rentals of demo equipment, which give you the best equipment at reasonable prices.
I am sure you would be best to take lessons. You need to know the basics before you venture out on the slopes. Start out on the easy slopes, and very important be sure you wear a helmet.
If you get hooked, there are often ski swaps early in the season, especially good for kids who are growing. At the end of the season there are usually good sales on equipment. If you really get hooked season passes are usually a good buy.
I hope some of this helps. If you have any questions I can either find out for you. or enlist someone who knows. My husband and I used to enjoy snow shoeing, and some like cross country sking. My knees keep me from doing much now.