Newbie having problems setting up Woocommerce

https://loseweighttogethealthy.com
I am not sure if it has something to do with “Your theme does not declare WooCommerce support” or not but I have the plugin installed but I have no checkout-pay page. When you get to that point you just get a white screen with nothing on it. I am not techie at all at this point so I would REALLY appreciate some help, preferably in English and not computereze. Feel free to talk to me like I am 6 because I think that is about where my knowledge base is.
TIA!