Marika and the Elden Ring

Hi, I'm having problems with the Marika e l’Elden Ring . We know that the first to arrive is Metyr in a world populated by dragons then the elden beast. Placidusax becomes a Lord with a God we don't know.

A sort of faith for the life and death cycle is born, praying for everything that is nature. This is the spiral tree (that Marika will then use to make the Scadutree become)

The God escapes or dies, Placidusax is waiting for her by getting stuck in time(?). The Hornsets take control of the situation, create a portal for the gods(?)

This portal for me never worked, or it worked and was created for the God of Placidusax. I don't understand how beings like Hornsets create such a thing. The Hornsets try to create a new God using the vessels and Numen inside. They can't. Marika chosen by the Fingers becomes Goddess, I think the Hornsets were consenting but they were later betrayed by first obscuring the portal and then using their spiral tree for the base for her Golden Order. The question is, where did Marika get the Elden Ring. Did he steal it from Placidusax? Was it given by the Fingers to you? After the death of the first God, had the elden ring remained at the portal?