How can I connect the "buy now" on my landing page to the checkout cart?

I’ve used unbounce to make sales pages for my website. They have a big buy now button…

but how do I connect that with my wordpress.org woocommerce site?

What link should I give it so that it knows to send them directly to the payment page and knows which product they have?

The sales pages correspond to products on the website. Do I use URL parameters? Special links?

Please help. Thanks!

p.s. Please note the website just redirects to another website. To see an example product, please go to http://jenniferparker.org/product/save-the-clock-tower-photo. To see an example landing page, please go to http://jenniferparker.org/limited-time-sale/

https://wordpress.org/plugins/woocommerce/