All the service lights are lit up on my 2008 hyundai elantra widows radio breaks and power steering aren't working

Usually it indicates the alternator is not charging. Get yourself a volt meter that plugs into the cigarette lighter. Read the voltage before and after you tart the car. The voltage should go up from 12v to 13/14v. Keep an eye on it. If it slowly goes down, then the alternator needs to be checked.

The new alternator is not producing power

Need to have a repair shop diagnose the
steering system
Can't guess at vehicle problems without the
patient

The most widespread Hyundai recall, affecting up to 531,894 2005-2008 Accent, Azera, Elantra, Entourage, Santa Fe, Sonata, Tucson, and Veracruz models, is NHTSA Campaign 09V122000. It is focused on a malfunctioning stop lamp switch that may prevent brake lights from illuminating when the pedal is depressed (the same switch may also cause them to stay lit after the brakes are released).
Owners of affected vehicles may contact Hyundai Customer Service at 1-800-633-5151, call the NHTSA Hotline at 1-888-327-4236, or visit SAFERCAR.GOV

Hyundai has electric assisted power steering, not hydraulic, and I know the
new Sonata has some steering issues. Better bring it into Hyundai especially
since you're still under warranty. Don't fool with this, since the car is extremely
difficult to steer if you loose the assist.

Your Electronic Power steering has an issue - have a shop look at it for you before it fails completely.

Check fuses, bulbs, wires and brake switch (back side peddal).

Keep us updated.

Open the fuse panel and take out the fuse for the radio. After about 30 seconds put it back in.

When car stalls check for spark, if no spark check crank sensor. If there is a crack in the sensor when heated crack opens and car will stall

As you can see in this wiring diagram, power supplied is series/parallel