@johnse is correct that the normals of the model seem to be incorrect, however they don't affect slicing. Normals are only used for visualisation.
From the looks of it, your model is not "manifold". I think you modeled the torus and the cylinders and just moved them so they look like they make a whole. However, you did not join (or union, or boolean, or something else, depending on the modeler you use) the shapes so they don't actually form a single geometry. As is, the cylinder geometry just extends into the torus geometry, so you have what is called "internal geometry".
When slicing, Cura makes cross-sections of the model. Looking from the outside in, the first edge-loop it encounters will be an outer wall. Going in, if it encounters another edge-loop, that will become an inner wall of a hole. Etc. In your case, because you have (sub)objects intersecting eachother, Cura simply looses track of what should be the outside and what should be the inside.
Long story short: Cura fails to meet your expectation because your model is "wrong". Just because it displays well does not mean that it is suitable for printing.
The red on the rop of the ring shows at least part of the problem. cura is thinking it needs to support the top of the arch. Normally support should only show on bottom surfaces.
I suspect this means the normals of the mesh are reversed.
look in the marketplace for Mesh Tools.
Others can likely give give more explicit directions.
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