Everything works will turn over fuel pump works and has spark but will not fire tested fuel pump pressure with air to the fuel rail with canister and fuel pump worked good also tested all plugs and wires and their good as well but it still wont start ive been told to check the neutral safty switch

You need to determine if you have spark at the spark plugs and fuel pressure to the fuel rail. If you do have spark and fuel pressure I would look to the pick up in the distributor as that is what fires the injectors. If you do not have fuel pressure look to the fuel pump relay first, if it is good you are probably looking at a fuel pump. If it has no spark look at the coil or the crank sensor. If everything tests good then ECU.

1.6L or 1.8L vastly different engines... and EFI.
fuel to the rail , only means the pump is active , never good.
28PSI is minimum on all cars. 1psi will never start a car. ever
and the rail will shoot fuel, all day. it fruitless , unless the rail is dead.
see?
First the laws of EFI. (works all gas EFI)

1. all fuses good.
2. 12vdc to EFI system , below 10v is bad. (see lamps dim? bingo)
3. The PCM (EFI brain) will never inject if it sees CMP/CKP or spark primary dead. ever. so, spark is first.

that is double reasons, fuel cant burn if no spark and if ECU
thinks spark is bad it cuts fuel, (fire safety and fuel hydralocking reasons)

so you connect any scan tool to the DLC, OBD2 port , by knees.
and crank for 5 seconds, release key, no turn off
see DTCs (errors) for CMP, or CKP sensors (cam/crank?)
bingo
no, then you crank and look at the RPM PID , live data stream the scan tool, see RPM go to 250rpm cranking, good.
ok , PCM thinks all is good....

i then check the #1 injector with a NOID lamp
i crank it flashes, good.
if not , i do all injectors , if one fails the pcm is dead on this line.
if yes, all dont flash the PCM is seeing some gross errors. ask. why./?
if all flash, then the fuel rail is dead. and your rail test was useless.

until you discloses engine option (size) I cant give spec numbers.
i then connect my fuel pressure gauge $20 tool to the fuel rail test
port, and i get 10psi, FAIL
i check voltage to the fuel pump cranking, i get 8v, bingo bad wiring
or bad fuel pump relay.
say 10psi and 12v at pump cranking,
the pump is bad, or the filter clogged , or the fuel pressure regulator
is stuck wide open killing all legit pressure.

that is how i do it.
keep in mind the PCM cant see fuel pressure on most cars.
some newer cars have this sensors. (nice)
low fuel pressure,. renders the whole EFI , useless. just junk.

Check fuel pressure at test port, fuel filter and inspect the whole fuel line for kinks & crimps. If that doesn't work disconnect the fuel filter then use high pressure air to blow from the pressure regulator to the removed filter to ensure that the line is clear and open. Hook everything back up and check for pressure.

Three systems in engines:

Fuel delivery (fuel mixing with air to burn and making it to the spark plugs)

Ignition (lighting the fuel on fire)

Compression Building up pressure to fire the fuel
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It is possible your engine could have low compression if it has ever been run low on coolant or oil. The engine might spin or turn over but not have fire at the spark plugs. If you are correct that the spark plugs have fire but it will not "kick" or run then fuel delivery is where I would start. See if your fuel rail has fuel in it by pressing the fuel rail valve:

If you have fuel there under a good amount of pressure see if one of the plugs smells like gas after cranking. If so the problem is not the fuel, move on.
If you don't have fuel at the Schrader valve the problem is in the fuel pump and system.
refer to a manual on how to remove the pump from the tank and replace it. This problem has signs before it goes bad. Hard starts and running rough when hot.

Good luck

Air - not likely the problem ! mechanical cable controlled throttle body

Fuel- make sure there is gas in tank! fuel pressure test at the throttle body or rails, if no fuel check power to fuel pump: ignition power to breaker or fuse, relay , power to pump at 3 pin connector near tank/frame rail on drivers side, - if pump is runniig but insufficient pressure, check for mechanical restriction: plugged filter broken or pinched line, plugged pickup tube in tank. if good pressure to rail or body, check ecm : diagnostic codes, fused power, ecm tells injectors when to open, dependent upon several sensor parameter inputs.

Spark- ignition - coil-distributor-ignition module (or coil packs)- wires-plugs-ignition module (signals coil to discharge, mounted beneath distr cap) work backwards from plugs.

start with the basics check for fuel fire and air check fuel peressure with a gauge should be 50 - 65psi
pull spark plug wire and place near ground if no spark in crank sensor or coil pack ensure air filter is cleaned

on fuel pressure if low check fuel filter pump may be working and cant get to fuel rail but could have damaged pump the fuel pump is controlled via crank sensor signal so no crank sensor signal no fuel

If you have spark and fuel (either via the injectors or spraying fluid into the intake), and still no evidence of firing, it suggests your valvetrain may not be working. If the valves can't open, the fuel cant get into the cylinder.

Do (or have done) a compression test. You may have a broken timing belt/chain.

A typical engine needs mostly just gas and spark to run (besides air of course)
Sounds like the engine is not getting one or the other.

Fuel goes from fuel pump, to filter, to fuel pressure regulator, to fuel rail, to injectors.
You can test for fuel pressure with key on, at the fuel rail. There will be a test port on the rail that you can put a rag on top and push in the valve to see if there is pressure. (or use pressure tester)
If there is no pressure, check that fuel pump relay is working. (you can use an ohmmeter on relay to see if there is resistance). You can also test power to relay and to the pump with a voltmeter to see if pump is getting power. Or turn key to ON position and listen to see if you hear the pump turn on.

If you have no spark to any cylcinders, the crank shaft position sensor may be faulty which is very common in GM vehicles.

You can use an ohmmeter to test the sensor itself.
You can also get a spark plug tester to see if there is spark to each cylinder.
You can also remove one spark plug, plug back into plug wire, lay on top of engine so spark plug diode is 1/4" away from metal surface. Have someone else turn engine over while you look for spark. Do this to each cylinder.

Yes, it's more than likely your fuel pump.

You need to check the fuel press, the test port in on the rail, also run a code test on the ECM/PCM, this checks for trouble codes and also lets you know the computer is working if it tests ok.