Are you driven by power (would you like to be called a Founder, CEO), impact (what you have created has touched or is being used by x000 or x Million people) or is doubling your money something which fuels your passion? Usually, at the start you can get only one of these three - power, impact or money.
Once you've figured what fuels your passion or makes you jump out of bed in the morning, clarity of next steps will emerge.
If you are driven to be a founder, ceo - you will need to start finding a core team to build a company. New companies need a core team before it can get a core idea.
If you are looking for impact - have a look at ashoka.org or acumen.org. This might give ideas on developmental impact.
If you are looking to double your money, I'm clueless but I'm guessing there will be someone on wall street who knows the exact recipe on how to do it.