Complex sentence: They go to the museum first and discover the name "Charles Babbage," who had tried to invent two machines for solving mathematical problems that were basically and early computer and determine that Charnage is trying to build one of these machines.
Split into simpler sentences: They go to the museum first and learn of Charles Babbage, who had tried to invent two machines for solving mathematical problems-essentially primitive computers. They determine that Charnage is trying to build one of these machines.