What discoveries were made during the search for a way to India?

The first important event was the journey of Bartolomeo Dias, who in 1488 was able to go around the African continent and get into the Indian Ocean. Thus, he opened a direct route from the Atlantic Ocean to the Indian Ocean.
The second in time, but the first in its size and importance was the discovery of the American continent by Christopher Columbus in 1492.
From 1497 to 1499, the Portuguese navigator, using the route of Bartolomeo Dias, paved the sea route to India, so that the overland trade of Europe and Asia faded into the background.