Command & plugin.yml

Please help me! How to make it. For OP use only

1. Please explain some more (OP use only, please make it) thats not descriptive
2. You realy start to annoy me. In my opinion you post plugin requests rather than help questions
3. All code you show here is stolen
4. I'm not saying that too often: But please learn php
AND WHY WILL PEOPLE NEVER LEARN HOW TO USE THE SEARCH BAR

if($sender->isOP()){

}

A public plugin should always use hasPermission() over isOp() to check for player permissions. This is for in case the user wants to let non-ops use the commands, or other things, through a permission manager.

In plugin.yml, add a permission attribute to declare a permission. Then in the command entry where you put the description and usage, also add a line to define the permission as the permission you just added.
Like this:
https://github.com/PocketMine/DevTools/blob/master/plugin.yml#L13
https://github.com/PocketMine/DevTools/blob/master/plugin.yml#L22

Thankyou very much guys

You can set the permissions in the Plugin.yml like this for the command /info:

PHP:

...
Command:
        info:
        usage : /info
         Description : Info Command.

Permissions:
        info:
        Default : op
        Description : Info Command