Answer:
Spain and Portugal want to find a sea route to Asia because both country wanted to discover more trade and specifically Spain wanted to spread the Christianity around the globe.
Step-by-step explanation:
Also they wanted to break the hold of trade carried by Muslims and Italian by finding the trade routes to Asia. Portuguese searched for the route that went around the Africa.
Ferdinand Magellan's attempted circumnavigation of the globe during the attempt to find the route to Asia. It was the important voyage of exploration.