How to upgrade PHP?

[anon46092769]

Hello and Welcome.
At the moment, only PHP 7.4 is supported on free hosting, and PHP 8 is on the roadmap.
As for the blank page:

PHP 5.x versions will be removed soon

As of the 2nd of September, all PHP 5.x versions have been removed from free hosting, and all sites have been upgraded to PHP 7.4. The PHP version selector has also been removed (because there are no other PHP versions to choose from). PHP 8 is next on the roadmap regarding PHP versions, which will replace PHP 7.4 when that happens.