cannot launch Magento 2.3.3 on php 7.4.
Problem: magento/product-community-edition 2.3.3 requires php ~7.1.3||~7.2.0||~7.3.0 -> your PHP version (7.4.0RC4) does not satisfy that requirement.
How can I run it on Php 7.4?
Magento 2 hasn't added support for php 7.4
Check out Magento 2 release notes
Magento 2.3.3 now supports PHP 7.3.x (tested with PHP 7.3.8) and PHP 7.2.x (tested with 7.2.21).
Currently php7.4 is not added in magento.
So you can just install php 7.3 in addition to php7.4 and set php7.3 as primary.
Then you will be able to run your magento.
Eu forcei a instalação alterando o arquivo composer.lock na linha
Please follow the below to resolve this
For solution you can follow below links.
First you have to check your system which full-fill magento 2 system requirement.
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