What did prince asoka build in his kingdom to encourage his people to adopt buddhism? whom did he send to spread buddhism to other kingdoms and where it was spread to?

As a Buddhist emperor, Ashoka believed that Buddhism is beneficial for all human beings, as well as animals and plants, so he built a number of stupas. He also well spread Buddhism to neighboring kingdoms.

He is remembered for the Ashoka pillars and edicts, for sending Buddhist monks to Sri Lanka and Central Asia, and for establishing monuments marking several significant sites in the life of Gautama Buddha.