Kindness to people is a character of Prophets and pious people. The Qur’an reported the story of the Prophet Moses (peace be upon him) who helped two women when they came to water their flock. He went on and watered their flock. (Al-Qasas 28:24)
Also, Allah commands us to do good to others. Almighty Allah says,
“And do good as Allah has been good to you, and seek not mischief in the land.” (Al-Qasas 28:77)
“Surely Allah enjoins the doing of justice and the doing of good (to others)” (Al-Nahl 16:90)
“Do good, for God loves those who do good.” (Al-Baqarah 2:195)
The Prophet (peace be upon him) said, “Allah has decreed kindness in all things.” (Muslim) So, one should extend kindness to all people, even non-Muslims.