a new model based on that face, use the following workflow:

1. Select the faces

2. Press SHIFT+D to duplicate the faces

3. Press the ESC key to cancel the transformation of your duplicated

faces

4. With the duplicated faces still selected, press the P key

5. Choose "Selection"

6. Switch to Object Mode

After switching to Object Mode, a new object based on those faces will

be available for you to start modeling (Figure 3.21).

Figure 3.21 - New faces for modeling

If you cant select the new object, look at the Collections for a duplicate.