I need help to editi my plugin

PHP:

<?php

namespace Flsmers;

use pocketmine\plugin\PluginBase as P;
use pocketmine\event\Listener as L;
use pocketmine\utils\TextFormat;
use pocketmine\utils\MainLogger;
use pocketmine\event\block\BlockBreakEvent as BBL;
use pocketmine\level\sound\PopSound as Pop;
use pocketmine\level\particle\ExplodeParticle as Explode;
use pocketmine\block\Block;
use pocketmine\math\Vector3;
use pocketmine\item\Item;

class Main extends P implements L{
   
    public function onEnable(){
        $this->getServer()->getPluginManager()->registerEvents($this,$this);
        $this->saveDefaultConfig();
        $this->getServer()->getLogger()->info(TextFormat::GREEN."[DropInStone] Włączony!");
    }

    public function onBreak(BBL $e){
        if($e->getBlock()->getId() == 1 && mt_rand(0,$this->getConfig()->get("t1-chance")) == "1"){
            $p = $e->getPlayer();
                        $p->getLevel()->addParticle(new Explode($e->getBlock(), 2));
            $p->getLevel()->addParticle(new Explode($e->getBlock(), 2));
            $p->getLevel()->addParticle(new Explode($e->getBlock(), 2));
            $p->sendMessage("§a • Wydropiłeś z stone'a - Coal • ");
            foreach($this->getConfig()->get("t1-loot") as $loot){
                    $p->getInventory()->addItem(Item::get($loot,0,mt_rand(1,$this->getConfig()->get("t1-item-max"))));
            }
        }
        else{
        }


How to add exp Stone's break and get 0.2 exp?

PocketMine does not have an experience API as far as I am aware. So you will have to handle it via direct packets to the players.

Yes it does: https://github.com/PocketMine/PocketMine-MP/blob/master/src/pocketmine/entity/Attribute.php
To change experience:

PHP:

$player->getAttributeMap()->getAttribute(pocketmine\entity\Attribute::EXPERIENCE)->setValue($value);

To change experience level:

PHP:

$player->getAttributeMap()->getAttribute(pocketmine\entity\Attribute::EXPERIENCE_LEVEL)->setValue($value);

Why :sob:

https://github.com/PocketMine/PocketMine-MP/blob/master/src/pocketmine/entity/Human.php#L217
https://github.com/PocketMine/PocketMine-MP/blob/master/src/pocketmine/entity/Human.php#L225

I need add loot lvl exp for drop stone

@Hotshot_9930 already told you what you need to use.

What? Loot lvl? Sounds like a feature you must code on your own.