Let the ice floor spawn under you in Minecraft?

How can you spawn an ice floor under you in Minecraft like in this video? ( is that a mod or is it different?

That should be n plugin.

have your own server and then load the plugin that does that onto the server

How is the plugin?

So I don't know the plugin. This is such an extension for the server. You enter a certain command in the chat and then the plugin is started

Simply e.g. Leather shoes with the enchantment ice skater

If not just in the water but everywhere, then "/ execute @a ~~~ fill ~ 1 ~ -1 ~ ~ -1 ~ -1 ~ ice

If I enter that it doesn't work.

What does the command block say?

So you can take a picture of the command

They always code that themselves. I won't find that.