<p>I am Attempting to print this, from Blender
<a href="https://i.stack.imgur.com/kKdun.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/kKdun.jpg" alt="enter image description here"></a>
But Cura decides to fill in the middle part of the model. 
<a href="https://i.stack.imgur.com/1fj3T.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1fj3T.png" alt="enter image description here"></a>
I exported and imported the model from an STL file.</p>

<p>If anyone can answer this, that would be greatly appreciated.</p>

I would recommend using an actual CAD/CAM program, such as Autodesk Fusion 360, instead of using a 3d model program. Not only will this be able to directly export you finished model to Cura, and the models are made in a way that works with a 3d printing slicer, there will be more help around 3D printing for it.
Although it is slightly difficult to use to start with, as you become more proficient, it is a very powerful tool to have. . Fusion 360 is free for hobbyists or students. See this link for help activating:
https://www.autodesk.com/campaigns/fusion-360-for-hobbyists
.
Another option would be SolidWorks, although you do have to pay for this option, but it is much simpler to work with in my opinion.