Set Certain Shopify Product Variant as Default -- with JS/Jquery

I have a task for shopify I wish to work on, currently when you check this product: [login to view URL] it opens with no selected variant. But I want functionality to select a variant that is selected directly when you land on the page. For now by default, I want the product variant to be selected to ‘Brown Combo’ So when you land on page, or refresh it shows the Brown Combo selected and only show the 4 photos for the Brown Combo Variant. This is how this product should look when you land on it: I need you to note all the files you work on, but please work in product template: [login to view URL] and file: [login to view URL] Password is ‘leefy’ Let me know if this is something you can assist with