Q: Why won't the starter motor engage and turn engine over. Also, the clutch pedal won't move and the clutch is partly engaged but slips.

If the clutch pedal is not moving and the clutch is partially applied, then the clutch release bearing may be damaged and the fork is jammed into the clutch forcing it to slip.

For the no start condition on the starter, try tapping on the starter solenoid and see if the starter engages. If the starter does not engage, then remove the starter and see if it engages without the engine. If the starter does engage, then try to crank the engine over by hand and see if it turns. If the engine does not turn, then the bearings may be locked up or there could be an issue inside the engine. If the engine does move, then the starter needs to be replaced. For the brake lights not shutting off, the brake light switch could be applied as it may be not connected properly on the brake pedal. Check to see the location of the brake pedal light switch and adjust the location to relax the switch. If the switch is relaxed, then the brake light switch would need replaced.

I recommend seeking out a professional, such as one from Your Mechanic, to help you with the no start and clutch issue.