Whats kind of oil does this car take on 2001 Mercedes-Benz SLK230

what type of oil should i use. Is a 10w30 synthetic fine

Mercedes recommends Mobile 1 full synthetic. Do you still have your owner's manual? It will specify the weight.
I'd give your local Mercedes dealership service department and a European specialist shop a call to ask them. The answers for these cars in the online forums are all over the place, and the manufacturer is the best resource if you don't have the book.
not sure didnt come with a book when I bought it