I don't think you'll get any useful advice here. You should be able to come up with your own idea if you want to be a successful businessman anyway. That's how it works usually. Depending on other people's ideas is not a good way to start things. You'll mostly get generic crap like "start a casino", "start an exchange", "sell stuff" etc.

What are your skills? Do you know coding? Are you good at writing articles? (maybe blogging is for you then) What are your hobbies? If you don't give us any info about yourself we can't say much and it would be smart not to share your private data.

As you see, knowing what you like and what you don't is a great place to start because we always want to have a business which we like.

A vegetarian guy won't become a good butcher for example.