A lot of people out there who want to start a startup often retract for mainly two reasons. Sometimes because they actually don't want to take the risk of starting a business. Sometimes because they don't quite understand the process, how a startup works, how different it is from starting a regular business. Basically, there is no difference between a startup and a regular business. We call early stage companies startup except one thing: startups are high growth companies.
It means, growth is what separates a startup from a regular early stage company. Being said that, starting a startup is no different from starting a regular business. One thing you have to keep in mind that you have to choose a relatively difficult problem and a big market.
The infographic below, prepared based on an essay of Paul Graham of YC and designed by Funders and Founders, explains the process of starting a startup pretty clearly. It breaks down every possible step and illustrates it brilliantly.