The Amazon page doesn't list any useful specs but if there's nothing extremely unusual about the bike, you'll need a 700C road wheel, quick release, for rim brakes, probably a 130mm hub.

Because it's a 7-speed you can use either a freewheel or a cassette. A wheel will accept either one or the other, so check which one and buy the appropriate one with a similar range of cogs to what you currently have. A freewheel wheel will be cheaper, but may be harder to find. If you buy a cassette wheel, you will also need a 4.5mm spacer to put behind the largest cog. A cassette also requires a special tool to install, while a freewheel only needs tools to remove.

In addition to that and the tire you'll also need a tube and a rim strip or rim tape.