How did the events in eastern and southern Europe of the 14-15th centuries affect the medieval world?

The changes were as follows:

The Byzantine Empire fell into decay due to internal conflicts, wars with neighbors and the invasion of the Balkans by the Turks. In 1453 it was captured, and in the next 20-30 years the Turks drove out the Venetians and Genoese from the eastern Mediterranean Sea and from the Black Sea, they monopolized trade with India and Persia in their hands. The South Slavic states, Serbia and Bulgaria also disappeared from the world map.
Completion of the Reconquista in the Iberian Peninsula by 1492 and the beginning of the era of great geographical discoveries. As a result, by 1498 the Portuguese reached India, and the Spaniards in the same year founded their first fortresses in the Caribbean.
By 1500, the Moscow principality had become a full-fledged participant in European politics.