""Preceded" means "went before" or "came before." If my birth preceded yours, it means my birth came before yours. If your death was preceded by mine, it means my death came before yours.
In the obituary, it means that your grandpa's parents, daughter and sister all died before he did.
yes, it means thy died before him.
Yes, that means that his parents, daughter, and sister died before him.
that his parents, daughter, and sister died before him