Torus Tool

Ribbon menu Bodies tab Solids container Torus Tool
or
(Classic) Build Bodies/Geometry Torus Tool
Creates a solid circular ring. You draw the ring from the center outward. By default, the Torus tool makes the radius of outer ring (minor radius) 25% of the inner ring (major radius).
You can also specify the minor and major radii before you draw.
Learn about Creating a Torus.
 
For the option:
Do the following:
New Part/Add to Part/On Ground
Select either:
New Part - Creates a new part.
Add to Part - Adds the torus to another part in your model.
On Ground - Adds the torus to ground.
Tip: Add geometry to ground if the geometry does not move or influence the simulation of your model. For example, if you are simulating a car driving around a race track, the geometry that defines the race track can be added to ground.
Minor Radius
If desired, select and enter the inner radius for the torus.
Major Radius
If desired, select and enter the outer radius for the torus.
 
Note:  
Two hotpoints appear on a torus after you draw it. One controls the centerline of the torus’ circular shape and the other controls the radius of the circular cross-section. For more information on modifying geometry using hotpoints, see Using Hotpoints to Graphically Modify Geometry.