1: Sugar, which is made from sugarcane, was a rare luxury in Europe, and it's important that huge profits for Portugal and its colonies. Plantations were needed to grow and process large quantities of sugarcane for a lucrative sugar trade.
2: Europeans enjoyed their sugar and were causing the inhumane Atlantic slave trade. The conditions for enslaved people on sugar plantations in the Caribbean were especially brutal. Driven by profits, plantations owners saw enslaved labour as a less expensive way to produce sugar.
3: Plantation owners, merchants, traders, and Europe's rulers all made money from the transatlantic slave trade. The effects of the Africans were disastrous: many died or were subjected to brutal treatment, whole communities and cultures were destroyed.
4/5: They might have set up a system in which you have to work for food.