One of the first things I did after getting my driving license was fly to Lisbon and rent a car there. At the time, you left the airport by merging onto a four lane roundabout with essentially no lane markings with people driving like maniacs and 5 or so exits for different highway directions. At the end of that vacation, I was driving a lot more confidently. But I wouldn't recommend that Darwinist approach to learning how to drive in the real world.
When done properly, multi lane roundabouts can be quite efficient. They are common in Europe as an alternative to just having a lot of traffic lights at any junction. Some of the bigger ones can also have traffic lights.
A good guideline is that if you need to go 3 quarters around, you probably want to be in the left most lane when you enter and move right as you progress. In case of doubt, just go around a second time. If you are too far right, merging left is something you want to be careful with and not necessarily legal in some places. But it's not that different from sorting into the wrong lane for a crossing. You kind of commit to where you exit before you enter. Usually the signage should help.
The most annoying thing about roundabouts is the navigation endlessly going "At the roundabout take the second exit" (i.e. go straight on), which gets really annoying if you are on the ring road of some city that has roundabouts every few hundred meters. Which accurately describes a lot of smaller cities across Europe these days. Safe and efficient. But also tedious. If in the Netherlands, beware of your right hand dead angle and be on the lookout for scooters, e-bikes, etc. when you exit a roundabout. You are supposed to yield to them and they can really come out of nowhere.