Most, if not all retail-purchased chains will be of sufficient length for a cruiser bike. And in order to fit all the bikes, the chain you will buy will most likely have extra links in it that the seller assumes you will take out. There's too many variables for the chain manufacturer to take into account, like make, model, year, frame size, chain ring size, third party supplier chain ring size, manufacturer's rear cog size, third party rear cog size, etc, etc, etc. It's cheaper for the chain makers to send everyone a chain slightly longer than what they'll need rather than to produce 50 different offerings of what is essentially the same product.
So to answer your question, the chain you are looking at is probably the right length, and then some. For any of the adult framed bikes with 26 inch wheel sets I used to build before getting sick, the chains I bought from the LBS or from online sources always had to have out a couple of lengths removed to fit properly.
If you're going to be doing this a lot, get a good chain tool. A cheap one will not work as well.