01. As your WooCommerce registration page is missing. Please navigate to Woocommerce > Settings > Account and privacy > enable Allow customers to create an account on the “My Account” page
Also you need to make sure that you have my account page with the below shortcode:
That specific account page must be selected from the “My account page” dropdown from WooCommerce >> Settings >> My account page.
Screenshot for clarification:
After doing this also check your dashboard pages after clearing your site and browser cache.
02. Our theme has two main categories of buttons and you can configure their design via Theme Settings -> Styles & Colors -> Buttons. From there you can set their style, background color, and text color scheme.