>>349896442
it pretty much has 4 sub-sections you need to do
water level
box room
light room
mannequin room

which all lead up into the final water level pt2 and then the ending scene
you can do those 4 sub-sections in almost any order you want (crowbar for water level, lighter for light room, letters for box room -> you find all of those instantly. only mannequin room is locked behind the box room and light room first half), so depending on whether you play alone, with 2 people, 3 or 4, you can complete the devouring in a different order
(however if you're speed running there's a clear opinion on which order of doing those is the fastest)