Open Windows search and type "%appdata%". The file explorer should open a new window with the path
C:\Users\[Username]\AppData\Roaming.
Navigate to the folder named ".minecraft" and in that to "saves".
Open the Singleplayer .zip file and extract the contents into the saves folder.
Start Minecraft and you should see the world in your Singleplayer selection screen.
Older Minecraft versions than the world can usually not play the world.
Open the server .zip file and extract the contents to somewhere.
In the folder should be a .jar file that has a name like "minecraft_server", "spigot-1.XX.X" or similar.
Sometimes it works to just double click that file to start the server.
If that is not the case, please open a command window and change to the folder where you extracted the
zip.
Example "cd C:\Users\jonat\Desktop\Minecraft\1.18.2testserver".
Run "java -Xms#G -Xmx#G -XX:+UseG1GC -jar spigot.jar" where the # has to be replaced by the minimum and
maximum amount of ram you want to give the server.
Go to the Multiplayer menu in Minecraft and connect to a new server which has the adress
"localhost".
The Dynmap is accessible in browser with the url localhost:8123.
Please make sure that you have an appropriate version ov Java installed. You can check that in the
command window with "java --version".
1.16 requires Java 16 and 1.17 and 1.18 require Java 17.