My 98 Sentra does not turn over

It is not a problem of sensor as it is not showing any dashboard light, neither it seems to be a problem of battery as battery gets charged after driving if the alternator is working fine or otherwise it won't start at all after overnight standing. It could be a problem of starter solenoid as it has copper windings and when the copper winding gets old it functions intermittently. I am sharing a video that will explain it better.

NEED A BATTERY WITH MORE COLD CRANKING AMPS.

start by following your negative wire off of the battery it should go to metal on the engine or to the frame (a fender bolt is ok) try putting your negative jumper cable from battery to any metal on engine. turn on headlights wiggle cable to make sure you have good connection, see if head lamps come on. If lights come on replace ground cable from battery. if not remove jumper cable and start looking at positive cable.check it for a good connection to battery and also to cable . if connections are good there follow the positive cable down to the starter solonide.you should check your battery voltage at this connection. If its good and the connection is good but you still have no power replace starter solonid.. I suspect the positive cable going to the starter will be bad or the connection will be bad.

I assume you checked the fuel pressure and it is normal.
Are the spark plugs getting spark when it fails to start ?
Are you getting injector pulse from the computer ?
Any trouble codes stored in the computer ?

Do the lights on your dash come on like they should?
IF SO, try starting the vehicle in neutral!

The Ignition switch could be bad. but see if its a bad ground first.

It sounds like the starter. Take a rubber mallet or a small hammer and beat the starter a few times not really hard like it owes you money, but hit it good. If the car starts after this your starter is stuck and needs to be replaced. Now this might not work, the starter can be so bad that nothing like this will help. Take it off go to your local parts store and they can test it for you. There should not be a fuse anywhere on the starter wire. O yeah make sure the battery is good and charged up. A low battery will do this too.

good day Sir, try to check the spark plugs and the coil hope this will help you.

take the car to autozone or pepboys, have them take a look, most likely the cop is right. may need anew starter.

Check that the battery connections are tight and secure. If yes, check the starter motor connectors and check current to the starter while the ignition key is turned. If there is no current, try wiring the starter directly to the battery. If it turns, then the problem is in the wiring or it could be the starter motor fuse. If the starter does not turn, remove the starter and take it to an auto parts store for testing.