1.find a map and download it if it brings you to adfly wait 5 secs then top right there will be a skip button click that
2.once the map is downloaded open the zip file then the first folder there youre gonna wanna pull out to your desktop [this has to happen]
3.type in %appdata% in the search bar [bottom left] go to roaming then to .minecraft
4. there will be a thing called saves open it and there should be all your worlds
5.drag the file that you pulled out into there
6. open minecraft go to singleplayer and it should be there


hopefully this helped if it did leave a diamond and thats me for now

:)