To check if the engine is seized on a 2006 Honda Civic, you’ll need to turn the crankshaft pulley bolt. Here are the steps you should follow:

1. **Safety First**: Ensure the vehicle is in park (automatic transmission) or neutral (manual transmission), and the parking brake is engaged. Disconnect the negative battery terminal to prevent any accidental electrical issues.

2. **Locate the Crankshaft Pulley**: The crankshaft pulley is located at the bottom of the engine, usually on the driver's side in a transverse-mounted engine layout, which is common in Honda Civics.

3. **Socket and Wrench Setup**: Use a socket wrench with the appropriate socket size (typically a 19mm for Honda). A breaker bar or a long-handled ratchet can provide additional leverage and ease turning.

4. **Turning the Bolt**:
- **Direction**: Turn the crankshaft pulley bolt clockwise (tightening direction) when facing the engine from the front of the car. This is standard for most engines to ensure you do not accidentally loosen the bolt, especially if you are only checking for seizure.

5. **Checking for Movement**:
- Rotate the pulley slowly and steadily to see if the engine turns. If the crankshaft turns without excessive resistance, your engine is not seized.
- If the pulley does not move or you encounter extreme resistance, the engine may be seized.

6. **Listen and Feel**: As you turn the crankshaft, pay attention to any unusual sounds (such as scraping or grinding) and feel for smooth rotation. Normal resistance from the compression of the engine cylinders is expected.

7. **Additional Checks**:
- If you suspect hydraulic lock (where engine cylinders are filled with fluid), you may need to relieve this pressure by removing spark plugs and trying to turn the crankshaft again.
- Check for any visible damage or obstructions in the engine bay and around the crankshaft pulley.

These steps should help you determine if your engine is seized. If the engine doesn’t turn over or is extremely difficult to turn, it might be seized, and further inspection or professional assistance might be required to diagnose and resolve the issue.