Boydie talks a lot of sense.
You have to start off with not just good songs, but fantastic songs, that people will gladly part with their hard earned cash, then you have to decide what is successful, quantify what you are prepared to do to get there, often nowadays bands get told exactly what they can expect from fame, fortune, commitment, how it feels to have a different relationship with friends, I would encourage you to listen to Ed Sheeran on Desert Island Disks, he reveals a bit of what it's like.
The pedigree of fame and fortune isn't a good one I'm afraid to say. It's also something that you can't give back when you don't like it anymore.
If you are really successful then you end up letting lots of people down, Korea wants you, but so does LA, and Germany, Japan...
You can get there but it helps if you have all the support, the marketing, advertising, promo/merch, radio/TV airtime, not just in the UK, if you play Country then you might need to tour the southern USA, that costs a shed load of wallop, and if you haven't sold any units, then you have to borrow it against future sales etc.
But first you need songs that are brilliant, and an image that suits the music, and that people can relate to in any language, you whole persona needs to be a cross between a brand and a Hook, and companies will treat you as such.
hope this helps
cpm