How do I create a topdown 2d level?

Hi!

I'm starting to play with Unity 5.3 and I'm trying to do a topdown 2d shooter. I've got the movement, player shooting and stuff down. I even have health. But I have no idea how to create the levels I'll be playing in.

I've tried to find tutorials, but they are all for 3d or FPS

I'm trying to achieve a look like this:
http://i40.tinypic.com/357hv5u.png

I'm suspecting this is using tile or something. If anyone has any good suggestions, links or how-to's for creating levels, I would greatly appreciate

 

This tutorial might be of some help. It shows you a pretty good way to make 2D top down levels in tutorial #6 and #7.

 

Thanks!!!