Cocoon

Cocoon has 11 total collectibles known as Moon Ancestors. These can be acquired as you play through the game, or easily mopped up using chapter select once you finish the story. They are most often hidden just off the main path; may involve a small and simple puzzle, and are unlocked with an interaction.
5:43 - 63% - Conduit
This can be done at checkpoint 63% when you take the orange orb to the left. Head across the bridge, down the elevator, and down to the bottom of the screen. Follow the pipe that leads to a bridge that can be activated using the orb to grab this.

Not my video but direct line to location.
Checkpoint is 63%

Gg

Check the guide below, you need to load at 63%


Timestamps:

00:00 Intro + 0-14% + Off the Beaten Path Achievement
04:49 14% - 17% + Pathfinder Achievement
06:37 17% - 24% + Mariner’s Branch Achievement
09:50 24% - 27% + Mesh Network Achievement
11:12 27% - 32% + Fundamental Changes Achievement
14:01 32% + End of the Line Achievement
14:40 32% - 46% + Skin Deep Achievement
21:45 46% - 52% + Different Destinations
26:26 52% - 56% + From There to Here Achievement
28:21 56% - 63% + Conduit Achievement
32:48 63% - 73% + This Has Potential Achievement
38:59 73% - 81% + Cryptographer Achievement
43:08 81% - 84% The Space Between the Stars Achievement
46:09 84% - 86% + A Perspective on things Achievement
47:26 86% - 90% + Daybreak Achievement
55:13 90% - 97% + Loophole Maneuvers Achievement
1:00:23 97% - 100% Cosmic Architect Achievement

Continue through the main story progression until you obtain the pink orb; the one that teleports to you when you interact with other objects (different from the purple one you obtain early in the story). Go through a handful of different tasks with this orb as part of the story.

You will reach a point where you place the orange orb, green orb and this pink orb all together into some sort of space ship. After riding this ship very briefly, it lands and the three orbs are placed in different spots pointing towards different trials.

The orange orb is in the south-west position. Follow the orange orb trial and you will end up in a section with one of the pedestals that follows you around, and a pressure plate which moves two gates on an upper ledge on the left side. This is the area with the Moon Ancestor and is a part of the main story.

In the south of this area is a large pipe that you can walk through. It's a hidden path that leads you to the Moon Ancestor.

CHAPTER 4 - CONDUIT ACHIEVEMENT

You unlock this by interacting with the Moon Ancestor in chapter 4, you can find this using this guide to help you get through all of chapter 4 to get all of the achievements on that chapter, the Conduit achievement drops just around the 13:40 mark.