how to create a stucture

I don't know, but I think you can look it up on youtube as KillerUnicorn has a lot of videos about MCreator. I believe you need to build the structure in your Minecraft world, and then use a program called MCEdit to select the structure and save it as a schematic. But I'm not for certain.

It's A Simple Process. You Have To Build A Structure In Minecraft (Unmodded).

Then Save The World And Exit Minecraft

Then Open Up MCEdit

Open Up The World With MCEdit

Use The Select Area Tool And Highlight Structure.

Save It As A Schematic

Open Up MCreator

Go To Natural Structures Or The Item You Want To Use To Spawn It

Choose The Schematic From Your Files

Done!

Small Note: MCreator Only Allows Up To 1600 Blocks So Be Careful.

I want to get a structure from a world in my test environment, how do i do that? I already have mcedit and its on my vanilla minecraft.

As far as I know, you can manually open level.dat files in MCEdit from any directory.

@Nuparuu00

This is true; I have set up mcedit on my computer to automatically load a world form an instance of minecraft started using the multiMC launcher. Yo just need to know the path to the level.dat file

Do structure blocks save as schematics aswell?

no, they save as nbt which can be used for structures, but you have to know how to code