What is business option after civil engg

I am a civil engineer passed out in 2017 from pvt college.

I want to start a civil engineering related business with almost zero investment. But what is that option for me.

@Ajoy - Welome to CrazyEngineers. It's good to know that you want to start your own venture. 

The only two business ideas I can think of that need zero 'financial' investment are the following -

1. Consultancy: You'll help existing civil engineering companies save costs in their operations. You could charge a commission for your services. 

2. Enabler: You help your clients with cheaper yet quality sourcing that helps them get things done faster, at cheaper costs. 

 That said, have you explored the markets and found out a need that you can fulfil? Most successful businesses start by identifying a market need and then offering better solutions than existing ones.

Do a survey; talk to existing business owners and understand their pain-points. In my opinion, talking directly to the Civil business owners around your current location would definitely be a step in the right direction. Plus, you could be sure to get your first client easily. 

Hope this helps.