How to use MOOSE to generate a layered square with circular void in the middle?

[Yulongggggg]

Dear developers, I am trying to use MOOSE to generate a mesh, which is a square with a circular void inside, can u tell me how to do it? Also, the square should be layered, i.e., composed of different blocks(rectangle shape), and how to assign different boundary names (apply to the boundary condition block. e.g., 'inner')

[GiudGiud]

I am trying to use MOOSE to generate a mesh, which is a square with a circular void inside, can u tell me how to do it?

You can use this from the Reactor module
https://mooseframework.inl.gov/source/meshgenerators/PinMeshGenerator.html
or this
https://mooseframework.inl.gov/source/meshgenerators/ConcentricCircleMeshGenerator.html
with has_outer_square set to true

then delete the central cirlcle using a BlockDeletionGenerator

and how to assign different boundary names (apply to the boundary condition block. e.g., 'inner')

Once the blocks are set you can use this
https://mooseframework.inl.gov/source/meshgenerators/SideSetsBetweenSubdomainsGenerator.html

[Yulongggggg]

Thank you! Could you please tell me how to generate a layered square mesh with inclusion inside? Which looks like this

[GiudGiud]

with the mesh generators I mentioned you should get a good start.
You can add subdomains 1 by 1 using this generator
https://mooseframework.inl.gov/source/meshgenerators/ParsedSubdomainMeshGenerator.html

how many layered subdomains do you need?