All of these extensions should be are enabled on all accounts. What makes you ask how to install them? Does your software think some of these extensions are not available?
Could you then maybe start with getting the actual error message and seeing what it means? There are many reasons why you may see a 500 errors, and missing PHP extensions are rarely the cause.
i activated the php error display, i get this: Warning : putenv() has been disabled for security reasons in /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/Config/DotEnv.php on line 152
Fatal error : Uncaught TypeError: Argument 1 passed to CodeIgniter\HTTP\URI::setScheme() must be of the type string, null given, called in /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/HTTP/IncomingRequest.php on line 616 and defined in /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/HTTP/URI.php:625 Stack trace: #0 /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/HTTP/IncomingRequest.php(616): CodeIgniter\HTTP\URI->setScheme(NULL) #1 /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/HTTP/IncomingRequest.php(184): CodeIgniter\HTTP\IncomingRequest->detectURI(‘REQUEST_URI’, ‘/htdocs/’) #2 /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/Config/Services.php(609): CodeIgniter\HTTP\IncomingRequest->__construct(Object(Config\App), Object(CodeIgniter\HTTP\URI), ‘’, Object(CodeIgniter\HTTP\UserAgent)) #3 /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/Config/BaseService.php(123): CodeIgniter\Config\Services::request(Object(Config\App), false) #4 /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/Config/Services.php in /home/vol2_4/epizy.com/epiz_27280245/htdocs/system/HTTP/URI.php on line 625
Hmm, yes, this is a known issue unfortunately with CodeIgniter and applications built with it. Since some time, they use .env files for configuration. Unfortunately, our servers have some security constraints that prevent this from working properly. We’re still looking for a way to make this work without harming the security of our platform. Until then, I don’t think it’s possible to use CodeIgniter or software built with the CodeIgniter framework here.