So I've been trying to bake a map of my sculpture but it always comes as full yellow/green ? I've tried use cage and multiple different settings
here's also the file https://drive.google.com/file/d/1KOcTC3wr_gMYZyUxeHSHiWhBL1lszuKD/view?usp=sharing
Hi Bruno. That looks like a Normals issue. Try recalculating normals (Shift-N) in Edit Mode for both the HiPoly and LoPoly models and try to bake again.
Yeah. I downloaded your file and had a look. You need to flip the normals of the LoPoly model.
Also, to use your normal map when it is successfully baked you should set the Image Texture node to Non-Color, then connect its output to a Normal Map node (found under Add->Vector->Normal Map), and finally connect the output of the Normal Map node to the Normals input of your Principled Shader.
I hope that helps.