Redirect New Users After Registration

Sends people to a page of your choice (for example a welcome page) after they register through wp-login.php.

Code

add_filter( 'registration_redirect', function () {
    return home_url( '/welcome/' );
} );

Change /welcome/ to the path of your page.

Install WPIDE on your WordPress site (it is free) and open Code Snippets.
Use snippet above adds it from the library in one click. Or copy the code into a new snippet with the same code type.
It is added inactive: review the code and settings, then switch it on.