Hello,

1. I have checked the site and the top header menu color is showing fine: https://ibb.co/7rzzF6y

2. I did not see any round button on the site: https://ibb.co/2ZWx8PZ

3. Sorry, I did not understand, what do you want to do with the button on the banner?

4. Sorry, this is not possible to move whole the text but you can try the below custom CSS code:

.woocommerce-notices-wrapper .woocommerce-message {
    display: grid;
}

Best Regards.