You will need to copy/paste it because it is a lot bigger than what it looks like

Here's the code your going to need to copy/paste into the custom world settings bar

{"seaLevel":1,"heightScale":684.412,"lowerLimitScale":512,"upperLimitScale":512,"depthNoiseScaleX":200,"depthNoiseScaleZ":200,"depthNoiseScaleExponent":0.5,"mainNoiseScaleX":80,"mainNoiseScaleY":160,"mainNoiseScaleZ":80,"baseSize":8.5,"stretchY":12,"biomeDepthWeight":1,"biomeDepthOffset":0,"biomeScaleWeight":1,"biomeScaleOffset":0,"useCaves":true,"useDungeons":true,"dungeonChance":7,"useStrongholds":true,"useVillages":true,"useMineShafts":true,"useTemples":true,"useRavines":true,"useWaterLakes":true,"waterLakeChance":4,"useLavaLakes":true,"lavaLakeChance":80,"useLavaOceans":false,"fixedBiome":-1,"biomeSize":4,"riverSize":4,"dirtSize":33,"dirtCount":10,"dirtMinHeight":0,"dirtMaxHeight":256,"gravelSize":33,"gravelCount":8,"gravelMinHeight":0,"gravelMaxHeight":256,"graniteSize":33,"graniteCount":10,"graniteMinHeight":0,"graniteMaxHeight":80,"dioriteSize":33,"dioriteCount":10,"dioriteMinHeight":0,"dioriteMaxHeight":80,"andesiteSize":33,"andesiteCount":10,"andesiteMinHeight":0,"andesiteMaxHeight":80,"coalSize":17,"coalCount":20,"coalMinHeight":0,"coalMaxHeight":128,"ironSize":9,"ironCount":20,"ironMinHeight":0,"ironMaxHeight":64,"goldSize":9,"goldCount":2,"goldMinHeight":0,"goldMaxHeight":32,"redstoneSize":8,"redstoneCount":8,"redstoneMinHeight":0,"redstoneMaxHeight":16,"diamondSize":8,"diamondCount":1,"diamondMinHeight":0,"diamondMaxHeight":16,"lapisSize":7,"lapisCount":1,"lapisCenterHeight":16,"lapisSpread":16,"coordinateScale":684.412}

If you need any other custom changes like dungeon spawn rate,biome changes/world changes,ore spawn rate,ore vein sizes,lvl said on which blocks can spawn and etc

If you need to give the Map a world border, just use this command:

/worldborder

There is really no need for a separate plugin. You could also check out this video that I found with a simple google search. It will tell you everything you need to know, plus more.

https://www.youtube.com/watch?v=hPp-EFa5jrI

Just remember that you must do this for each separate Map you may be running.
GoodLuck!

If your using the map for your server you will need to set the border on that server world (can't do it on the custom settings), and do you not want another custom changes?

I'm not sure if it will work but you can still try

Yes I can help you..I'm goin to tie you a code that you will need to paste into the custom world setting bar

Need any other custom changes? Like amplified, more dungeons, custom ore spawn rates and sizes (and where they spawn) and etc?

You want a map that has NO ocean at all?

I'm pretty sure you can define that in the advanced generation settings.