You can easily change your app's PHP version. This is a simple and powerful way to develop and test your WordPress with newer PHP versions before upgrading PHP.
How to Change PHP Version
Log in your Sellcloud panel, enter your Wordpress tab management page. Click the newly created Application name and you will be shown the app's details page. From this app's page, scroll down to PHP Version tab. In the pull-down menu select the php version for your app. Recommended to use PHP 8.0 or higher for Wordpress latest versions.