Generate New Flat world

How Do I generate a flat world? is there any settings/commands I can run out of the box?

 

You must use ManyWorlds

 

No need
If you only want to generate a flat world,you could go yo server.properties can change the item at "level-name" to another name
and do remember also change DEFAULT to FLAT at "level-type"

 

yeah I tried doing that but when I saved the world and tried to port it over to my server everything was bumpy again.

I just used the MyPlots plugin and put the blocks I wanted in the settings file