1993 Mazda Protege wont start, when I turn the key everythi

Sounds typical of loose or dirty battery cables. Also check the small black battery cable that's bolted to the body near the battery. Rust or a loose bolt can cause this too.

Caradiodoc

Here's another possibility, failed starter motor.

Have someone tap the starter while while someone else turns the key. You'll get those symtoms if the starter won't engage.

Very doubtful. If it failed, you wouldn't have a problem after installing the new battery until it too became run down.

Tell us what "normal" is. Some cars switch off a lot of stuff including most lghts during engine cranking. If the things turning off on your car are normal, there could be nothing more wrong than the starter Scotty Dee mentioned. However, the assumption is this isn't normal or you wouldn't have mentioned it as a symptom.

Start by using a cheap digital voltmeter to measure the voltage between the two battery POSTS, not the cable ends. It should be near 12.6 volts. If considerably less, the battery is discharged or has a shorted cell. Charge the battery for half an hour, remove the charger, then measure again. If the voltage is acceptable, hold the voltmeter probes on the cable ends while a helper tries to crank the engine. If the voltage stays high, look for a problem with the starter or its control circuits.

If the voltage drops a lot, double check the voltage at the posts. If it's not the same, the posts and cable ends must be cleaned and tightened.

Holler back with your findings so we can figure out the next step.

Caradiodoc