Answers for "composer detected issues in your platform: your composer dependencies require a php version ">= 8.0.0". you are running 7.4.28.%"

Composer detected issues in your platform: Your Composer dependencies require a PHP version ">= 7.3.0".

composer install --ignore-platform-reqs

Composer detected issues in your platform: Your Composer dependencies require a PHP version ">= 7.3.0".

composer install --ignore-platform-reqs

or 
 #add to composer.json > config
"platform-check": false,

composer autoload-dump