Why the warning light ignited and cannot be start

Please provide more information.

"I put the key in the ignition, turn it and the warning light goes out, I turn the key to start but there is nothing..." or

"I put the key in the ignition, turn it and the warning light goes out, I turn the key to start but there only a ticking/clicking sound..." or

"I put the key in the ignition, turn it and the warning light goes out, I turn the key to start but the engine only turns over and doesn't catch."

Have you checked your ignition switch? Generally it is located "behind" the keyhole. It is a cylinder shaped thing that has contacts that might be worn or dirty.

follow this steps.God bless you
When you turn the ignition ON before starting the car, the "Check engine" light is supposed to come on indicating that the engine computer (also could be called ECM, PCM, or ECU) is powered on. If the "Check engine" light does not come with the ignition ON, it's possible that there is no power coming to the engine computer (e.g., due to a broken wire, faulty main relay, burnt fuse, etc.) or that there is a problem with the engine computer itself.

I doesn't matter what shape it is, what matters is that it goes out. all dashboards do a bulb check when you turn on the ignition; that tells you that those monitor systems are ready. a couple of them like oil pressure and charging voltage need the motor running in order to decide whether to shut off or stay on and warn you of a problem.

The battery ran out of power because the alternator is not charging it.
Have the alternator output tested and take a look at the fuses.

Sounds like the ignition switch going bad.

Probable causes are; ignition system fault-spark plug(s), ignition wires, coil; Vacuum leak; Injector fault; high or low fuel pressure

that is your brake pad low warning light,you need to replace front pads asap...

That light means that you are setting the tire pressure guage. there is nothing wrong with the van.