If coming to drive in the UK please take care, I have twice met foreign drivers on the wrong side of the road.
Roundabouts are a great invention to keep the traffic moving at busy junctions. Observe to the right as you approach and give way to any traffic on the roundabout or entering from that side. There are some good YouTube videos that will get you up to speed on which lanes to use depending on when you intend to exit. ( see Ashley Neal for example)
(The CPS is currently trying to extradite the wife of an American diplomat who killed a young man by driving on the right and then fleeing back to the USA hiding behind diplomatic immunity)