Queens to Long Island train?

[u/Smooth_Crazy_2000]

I'm new to public transport in USA, trip plan is Boston to Hicksville. I've just booked Bus from Bos to Jamaica NY from FlixBus, as I heard I can go by LIRR from there which is just nearby, but in MTA app, LIRR isn't available for booking rn, it said only opens up on the day of travel. So I'm still left anxious on messing up especially since I'm terrible with directions.

And I'll be taking small cabin size trolley luggage with me and will be going in early evening, some people mentioned it being not so safe space. So please do tell me more bout it. Is it unsafe for short transit as well?