Hello and welcome.
Is the theft or security light on or flashing after you try to start it?
This does sound like all related.
The security dissables the fuel pump and the injector circuit. A common failure of the security system is the ignition lock cylinder. That is also called the passlock sensor. They can be very irratic at causing no starts. sometimes the light will go off, but still be in theft mode. A scan of the system may reveal a code like p2958, 2960, or b2958, 2960. These are telltale signs of the lock cylinder being bad.
If not a security problem, then you need to get fule pressure and injector pulse checked. Have ahd a few fuel pump relays cause this as well as fuel pump itself.
Proper repair is to replace the ign. passlock cylinder if that is the problem. there are some aftermarket systems that can bypadd the factory system, but i never personnaly used them. Here is a link to one such site.....