The Loft tool can create a 3D mesh surface between two or more curves. The curves define the shape of the resulting mesh surface. You must specify at least two curves.
Launch the Loft window from the sidebar.
Select at least two curves to start the lofting operation and press the Loft button.
Input curves for the loft must all be open or closed. Circles can be lofted only with other circles.
Pay attention to the direction of curves. Reverse them if necessary. You can turn on Preferences > CAD > Curve direction to visualize curve directions.