The car starts most of the time but occasionally will not start. Battery is OK, engine turns over OK. If I wait 30 minutes or more, it usually starts. Sometimes this is first time in the morning; sometimes it is random.
Are you always getting a good strong spark?
The next time it won’t start, try turning the key off and on (NOT start) for a few times waiting a few seconds at each ON position.
This lets the fuel pump prime the system.
If this doesn’t work, pop the gas cap off and with an assistant turning the key on, listen at the fuel filler pipe for a few second buzzing type noise.
If you know the pump is priming , but it still won’t start, spray a LITTLE starting fluid into the air intake WHILE CRANKING the engine over.
Do NOT over spray. If the engine fires up then dies, you MAY have a fuel supply fault.
Possible plugged fuel filter, weak pump, plugged injectors, a leaking fuel pressure regulator or an electrical fault not sending power to the injectors can also cause a no-start.
There are other things, but that MAY get you going.
Let us know how you make out.
Posting back with results always helps all of us.