Why all vendor folder go to app/code?
المحلول
Please download from the downloads section of the website. Or you can use composer
composer create-project --prefer-source --repository-url=https://repo.magento.com/ magento/project-community-edition=2.3.2 ./
Where 2.3.2 is magento version.
Do not download from git
Git version is for magento core development if you plan to submit pull requests to the magento git repo
لا تنتمي إلى magento.stackexchange