What must the deceased's relatives do upon his death, and what is Islamically correct in this situation, with evidence, to avoid falling into innovation or error?

Upon the death of a person, the relatives of the deceased should immediately undertake the following:

Close his eyes and supplicate for him, based on the hadith (definition) of Umm Salamah (may Allah be pleased with her). Cover his entire body with a cloth, except for a pilgrim in ihram (definition), whose head and face should not be covered. Expedite his preparation and removal for burial. Bury him in the country where he died. Promptly settle his debts from his wealth. If he has no wealth, then the state should bear it, or some people may volunteer to do so.