When i try to start the car it will not turn over. The battery is ok because the lights come on. I can jump start it ok. If anyone has any idea please help!

Check connections to battery.

If you have access to a voltmeter, measure voltage between the negative post on the battery and the engine when trying to crank - should be less than 1 volt: higher than this is probably poor earthing - check earth strap to engine or gearbox.

Also check battery voltage when trying to crank - the lights use a lot of current, but nothing like the ammount you need to turn over the engine.

If the battery is OK, and the wiring's OK, it's probably the solenoid on the starter motor, or bad a ignition switch.

I can't tell you the colour of the wire to the solenoid (probably red), as I don't have the diagram for a Uno, but it'll be the thinnest wire to the starter motor.
Take great care if you decide to apply +12 to it: be prepared for some sparks, as it's an inductive load. Also the engine may turn, if the ignition switch is the problem..

It might be your starter engine. When you earlier started the engine, did you hear a "scraping" sound about 1/2 second after it avtually started? If so, it's the starter engine.

Morten.