There are no castes in Islam. Q: 49:13 says:
O mankind! Indeed We created you from a male and a female, and made you nations and tribes that you may identify yourselves with one another. Indeed the noblest of you in the sight of Allah is the most God wary among you. Indeed Allah is all-knowing, all-aware.
Sayyed Ibn Tawus reports a hadith from Imam Ja'far al-Sadiq that if you wish prolongation of the life of your friends, your family members and yourself, recite the following dua:
Bay’ah is promising to follow and obey. It did happen during the time of pervious prophets like when Easa Jesus (AS) asked people from Bani Israel : Who are my supporters? His disciples replied: We are the supporters of Allah (3:52). That was just an example of Bay’ah.
wassalam
Any type of aggression against any human being , Muslim or non Muslim and even against peaceful animals or nature is very bad and Allah does not like the aggressors.
Wassalam
Wearing clothes that reveal the shapes of the body is not allowed for a Muslim woman unless the shirt is wide and cover all parts like a long jilbab or abayah.
With prayers for your success.
"O you who have believed, indeed, among your wives and your children are enemies to you, so beware of them. But if you pardon and overlook and forgive - then indeed, Allah is Forgiving and Merciful."