Hi jroj,
see: https://docu.ilias.de/goto.php?target=wiki_1357_Required_and_Supported_Software_ILIAS_7
or: https://github.com/ILIAS-eLearning/ILIAS/blob/release_7/docs/configuration/install.md#system-requirements
or: line 11-12 in your 'composer-error.txt'
to see, that ILIAS 7.2 does not run with PHP 8.0, but with PHP 7.3-7.4!
This is the very next requirement you have to fix...
see: https://docu.ilias.de/goto.php?target=wiki_1357_Required_and_Supported_Software_ILIAS_7
or: https://github.com/ILIAS-eLearning/ILIAS/blob/release_7/docs/configuration/install.md#system-requirements
or: line 11-12 in your 'composer-error.txt'
to see, that ILIAS 7.2 does not run with PHP 8.0, but with PHP 7.3-7.4!
This is the very next requirement you have to fix...