alex.test/app/Console/Commands/AddBalance.php

<?php

namespace App\Console\Commands;

use App\Models\User;
use Illuminate\Console\Command;

class AddBalance extends Command
{
    /**
     * The name and signature of the console command.
     *
     * @var string
     */
    protected $signature = 'user:add-balance {id} {balance}';

    /**
     * The console command description.
     *
     * @var string
     */
    protected $description = 'Add balance to user';

    /**
     * Execute the console command.
     */
    public function handle()
    {
        $balance = (double) $this->argument('balance');
        $id = (int) $this->argument('id');
        if ($balance == 0 || $id == 0) {
            $this->fail('Balance or Id must be non zero value!');
        }

        /** @var User */
        $user = User::find([ 'id' => $id ])->firstOrFail();
        $user->balance += $balance;
        $user->save();

        $name = $user->name;
        $balance = $user->balance;

        $this->info("User $name has $balance balance now");
    }
}