That's a huge question and not easily answerable.
So many things depend on this and depend on that and we don't know anything about you yet. How much you are willing to spend is a good place to start.
Another thing is to know where you plan on going?..the world?, locally?, the tropics? Will you be bringing along other people?..how many? Are you willing to learn how to sail and then do charters to get the practical experience? ...because you don't just get in a boat and take off over the horizon without enough experience to keep from killing yourself or worse yet, others.
It is much better to learn about cruising by doing baby steps in a successive and logical way.....much along the same lines as learning
how to fly.
Tip: Do all this before you buy a boat because without knowing how to sail and having no experience, you have no idea yet what type of boat will work best for you. We all have different needs and desires concerning a boat, and you have yet to learn what those are.
Have fun in learning