To ensure your sketch is "clean" for 3D operations (like extruding a Pad), you can use the Sketch Analysis tool found under the menu. This tool checks for: Open vs. Closed Profiles:

Color-codes your sketch to show its status: green (fully constrained), white (under-constrained), or red (over-constrained). Pro Tips for Efficiency

Similarly, you can use other sketch tools to create more complex profiles.