Extrude part

lukas_lukas768

I need advice. I'm new in 3d modeling and so is onshape. I'm learning on my own. I downloaded the feeder model from the thingiverse and I want to modify it a bit for myself.
I took the STL file to import it into onshape based on this video I copied the lines of the original model.
Video 
https://www.youtube.com/watch?v=b9K5f6zzb1k&ab_channel=JasonHitesman

Using the Line, 3 point arc tools, I created the interior of the model as you can see in the picture. Now I need to extrude it to keep it all on the surface, but I can't extrude.In the middle I have already modeled a cylinder in which there will be food for birds.

https://ibb.co/gJjH2bP

https://ibb.co/wCCML43

https://ibb.co/TKHDmLT

Thank you for your help and I apologize for my English.

john_mcclary

If you also draw the inner circle in the sketch it will extrude everything but the inner circle, like you want

You can also insert your images  in your post rather than uploading them to a 3rd party site

lukas_lukas768

john_mcclary said:

If you also draw the inner circle in the sketch it will extrude everything but the inner circle, like you want

You can also insert your images  in your post rather than uploading them to a 3rd party site

Thanks for help. But what you show me in the gif image I know how to do hole in the middle.

But I can't extrude the object you are doing hole in the middle. 

I fix that use fill function. But how you creat this gif ?