WordPress Tutorial: Regardless of whichever web hosting you have (Namecheap, Crazy Domains, etc), if you have access to the cPanel with PHP selector, you can easily upgrade your PHP version to the latest one (or as provided by the hosting). If you do not see a PHP selector on your cPanel means that you will have to contact your Hosting provider to upgrade your PHP version.

Namecheap, crazy domains, etc do provide the PHP Selector with the cPanel thus it is very easy to make any changes to the PHP version. However, also please note that while updating the PHP for your WordPress make sure you have a backup of your website and database and that all themes and plugins are up to date.