Complex sentence: While at the college, Amu realised that some of the students, including his classmates, owned steel bicycles so he set himself the task of building his own bicycle from wood, carving it from a wooden slab in the bush near the college.
Split into simpler sentences: While at the college, Amu realised that some of the students, including his classmates, owned steel bicycles so he set himself the task of building his own bicycle from wood. He carved this from a wooden slab in the bush near the college.