Create child theme after costumizing the original

Its always good practice to never edit your WordPress themes original files. I am referring mainly to the styles.css and the functions.php files.

Any changes you make there will be lost if you ever update that theme.

So yes, you definitely create a child theme. Any changes you make to the child them will overwrite the parent theme. When an update is performed to the parent theme, your child theme is still there and it is untouched.

Creating child themes is not a difficult task, its just time consuming and awkward. Using wp-cli, its just one command and its done.