Add to Cart buttons through embedded html

Hi hope someone can help,

I have a custom bike builder that i have built in html, basically In copying all the products cart features from the product pages, ie the options and the add to cart button. I have embedded the builder into the homepage and I need to be able to add to cart and direct the navigation to other compatible products.

I need to add to cart (which I guess is from an external URL into OC) and load the next URL all in one click.
Is there anyone that could source me the code to do this. It would be greatly appreciated.