Step 1: Login to your cPanel account.
Step 2: Click on the File Manger button under files section.
Step 3: Click “New File” at the top left hand side
Step 4: Create a new file "phpinfo.php" and ensure it is under /public_html folder and click “Create New File”
Step 5: Select and Right click on it and choose "Edit" option.
Step 6: Copy/Paste the following coding into phpinfo.php, then click Save Changes.
// Show all information, defaults to INFO_ALL
Step 8: To test the phpinfo, enter domainname/phpinfo.php in the browser.