Use New Component to create an empty component or create components from bodies.
Model 
Create
New Component
Model
Assemble
New Component
Patch
Assemble
New Component
Model and Patch New Component
Create an empty component:
- Empty Component
- Select this option to create an empty component in the assembly structure.
- Name
- Enter the name of the new component.
- Parent
- Select the component that will be the parent for the new component.
- Activate
- Enable this option to make the new component active. Any features created while a component is active become children of that component.
Create a components from bodies:
- From Bodies
- Select this option to create new components from selected bodies.
- Bodies
- Displays the number of bodies selected. Click the "X" to clear all selections.