With all shared and reseller hosting you can change your PHP version on the fly, for either the whole account or individual domains/subdomains. We offer all major versions of PHP from 5.2 through to the very latest (currently 7.2). To change the PHP version in use for your domain(s) you first need to login to the cPanel, see the below guide on doing this:https://hostpresto.com/help/hosting/troubleshooting-hosting/i-cant-access-my-cpanel/
Once logged in your want the "MultiPHP" option which can be found under the "Software" section, alternatively simply type "MultiPHP" into the search box at the top.
You should then be presented with the following screen, you can either select indidivudal domains on the account, or use the top checkbox to apply to every domain (please note, if you select your main domain the version will be applied to any domains within the public_html folder too):
Once you've selected your domain(s) you wish to change the version for use the dropdown/select box on the right to select your version, once selected press the "apply" button:
The change is instant, if you find your website does not support this new version use the same process as above to change it back to what it was previously.