1. You need file manager. Download it on plugin
2. Create new folder name it anything 'my-functions'
3. Create new php file name it 'my-functions.php'
4. paste and edit code below suit with your want
<?php
/*
Plugin Name: my functions
Plugin URI: https://orkedtouch.com/wp-admin/plugin-editor.php
Description: This is my functions instead on functions.php
Author: MUHAZA
Author URI:
Version: 2022.04.13
License: GPL
*/
// add your functions below