Welcome to the forum. As Hud says a bit of searching will go a long way. Also, visiting a liveaboard
marina would tell you lots when you start meeting people who are actually doing it. As far as liveaboard
boats go some are better for that purpose than others but you can liveaboard nearly any boat and make it work. It depends on what you can rid yourself of in order to do it.
Boats are usually designed for a specific purspose. Those that are meant to be liveaboards are not necessarily those you want to go to sea in so you'll have to make some compromises if you truly want to make an ocean crossing
I lived aboard a Mariner 35 Garden Ketch
that was also a great passagemaker. It didn't have near the interior
space as a more modern, for example, Islander Freeport
36 but the Mariner made it across the Pacific with no problems. Maybe the Freeport
would too but I know they have hull
join problems and leaks
that need to be repaired before a crossing is attempted.