import net.minecraft.world.level.block.Block;

import net.minecraft.world.level.block.state.BlockState;

import net.minecraft.core.BlockPos;

import net.minecraft.world.level.Level;

import net.minecraft.world.entity.Entity;

import java.util.List;

public class MyCustomBlock extends Block {

   public MyCustomBlock(Properties properties) {

       super(properties);

   }

   @Override

   public void neighborChanged(BlockState state, Level world, BlockPos pos, Block block, BlockPos fromPos, boolean isMoving) {

       super.neighborChanged(state, world, pos, block, fromPos, isMoving);



       if (!world.isClientSide) {

           List<Entity> entities = EntityHelper.getEntitiesAroundBlock(world, pos, 10);

           for (Entity entity : entities) {

               // your logic for interacting with entities

               // for example damaging entities

               entity.hurt(DamageSource.GENERIC, 5.0F);

           }

       }

   }

}