Add Minecraft Server Resource Pack | Spigot?

Suppose I have Spaxh 256

I want to set this so that every player who comes to my server gets a request if he accepts it, the resource pack is downloaded, but in the resource pack is only a file, for example, the Emerald looks like a ruby, so really just a texture, how do I do that?

That will not do.

You would have to download a texture pack completely, in which only one item is changed. That would be placed over the texture pack by a person.

Let's say the person has Spaxh as TP, so in this case, your desired texture pack (only the desired blocks changed, the remainder vanilla) would be superimposed over it and will be used with priority. The person can still see all the blocks except for those you set.

But the client can do it too