@redtree I take it that you bought this camera at a brick & mortar location. FWIW, it's hard to get good help these days at locations like Best Buy, etc, and more than likely, impossible at Walmart.
Your best defense if you're going to buy local, is to know all about the item you intend to purchase before you walk in. Then, just ask for it, and take it to the register.
As mailpup has said, any card of 32 GB and under should work. But, take into consideration the size of the files the camera generates. If you're shooting oh the highest quality, (either RAW or Jpeg), these files can be quite large.
At today's availability and prices it doesn't make a whole hell of a lot of sense to buy a smaller card, especially at the 32 GB level. I would consider 16 GB, the lowest capacity cutoff point.
Something I would suggest, is to have several cards, each with its own topic. This "pre-filing strategy", will make your life easier when you import the images into your favorite imaging program.
IE. "last week's trip to the shore", Granny's 100 birthday party, Bobby's graduation, and so forth.
I never import directly to my choice of program, (Photoshop Elements) but rather import to a separate folder, weed out the crap, then give the "keepers" to PSE.
As far as brand of card goes, I use SanDisk and PNY, exclusively
There is a bunch of crap out there in the lower echelon bargain brands, that I wouldn't trust to hold important photos