Yes; skating up hill on Chariot Skates is not a problem, you can skate up any hill that you can ride up on a bicycle. The steeper the hill is, the slower you will go. On a very steep incline you may nearly be walking up with your feet turned outward while you push yourself up with the side of the large wheel. This is similar to the way you would tackle a steep hill on inline or other skates. Bikes with gears have an advantage on hills and will go faster up hill.
For the beginner, skating up hill may seem easier and safer than going downhill. However, going downhill is a lot more fun once you are experienced and can maintain control and stop at speed.