Sorry, my English skill bad. I'm new to Blender. I have a steel barrel but in Eevee Render it look like shadow error, light pass through steel barrel. I don't want that. . Anyone can explain for me why? And how to fix this problem or I missing something in model progress. Thanks !
Select your light, and under Properties, check the box that says "Contact Shadows".
As you can see, however, a small amount of light still bleeds through. If this happens, it can usually be eliminated by giving your object more thickness. In the example below, I used a solidify modifier to make it thicker.
It seems like the only problem areas in your object are concerning the "bands". Make sure they have both inside and outside faces, and that they are correctly aligned with the rest of the mesh.
Lastly, though I cannot tell from your photo, it looks like your object may be mirrored on the Z axis. If this is the case, make sure the two halves merged correctly, and if you're using a modifier to achieve this make sure "Clipping" and "Merge" are enabled.