That changes when Ash decides to get high with a lady friend, and they once again read from the Necronomicon, releasing the Kandarian Demon onto the Earth.

Source: https://collider.com/evil-dead-movies-and-shows-in-order/

The Deadites in each film are brought on by people reading from the Necronomicon Ex-Mortis.

Source: https://screenrant.com/evil-dead-ash-mia-beth-crossover-necronomicon-setup/

There's brief footage of the kids at a lake house, so it's entirely possible that they got the original Necronomicon from the original cabin, though I doubt that's the original chainsaw boomstick.

Source: https://www.slashfilm.com/1160068/it-looks-like-evil-dead-rise-is-bringing-back-the-boomstick/

There's no mistaking that Momoko has reached into the Necronomicon to give Carnage this Cthulhu-inspired look.

Source: https://screenrant.com/carnages-most-terrifying-depiction-killer-symbiote-as-cthulhu/

Who put the Necronomicon there and for what reason?

Source: https://gamerant.com/evil-dead-rise-plot-holes-mysteries/