You can use WorldBorder for this, which is already available on Minehut. Though, as a word of warning, you should not be generating a very large amount as you can hit server storage limits doing that. I would suggest no larger than 5000 radius (10000x10000) just to be on the safe side. It may be better to consider trimming your world instead, to make room for the new 1.17 content when it comes out. Or, if you wish, change the level name in your server settings for a brand new world.