You need to have the Mollie Magento 2 module installed and configured within your Magento 2 installation.
composer require rapidez/mollie
If you're working locally and your environment isn't accessible from the web you need to disable the webhook setting as Mollie can't reach your environment. This results in getting the "pending payment" page after each payment.
You can publish the views with:
php artisan vendor:publish --provider="Rapidez\Mollie\MollieServiceProvider" --tag=views
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