If you want realism, many airlines fly KLAX to PHNL in a bunch of different planes from the 737 to the MD-11 (FedEx). I would go on Flightradar24 and look for this route and a plane/airline that flies it and just pick one.
Since you’re traveling west, if I’m not wrong, choose an even number altitude like 32,000, 34,000 or something.
I use fpltoif.com for my flight plans. My favorite is the SimBrief to IF feature but you can choose either method. The FlightAware to IF method is more simple.
Even if you fly on Live, if your connection goes out, you won’t be kicked off, but players won’t be able to see you until you reconnect. Your flight will continue as normal, so you can choose Live or Solo as you want.
Hope this helps!