There are lots of religious book that include religious teachings like Nahjul-Balaghah. Similarly books of narrations are also available like Al-Kafi, which consist of collections of narrations from the Infallibles. We advise you to read what relates to the general aspects of the religious knowledge like ethics, biography of the Prophet and the Imams and the narrations on the superiority of the Ahlul-Bait (peace be upon them) and their high rank. The details of the practical religious laws as explained by the jurists â€“ as they are the experts in this field â€“ are available. You are advised to refer to the treaties of the practical Islamic laws of the jurist that you emulate in order to know the specific rulings.
Yes, it is necessary for the Shia deceased to be given the ghusl by a Shia; if that is not possible and a Muslim that does not follow the path of the Ahlulbait (peace be upon them) is the only choice, then based on an obligatory precaution he should perform the ghusl himself and then do the ghusl on the deceased.