help with SHOPIFY store and having "add on" products once someone purchases an initial pong pack

Hello, I am running [login to view URL] currently. I need a developer to assist me with process and help implement changes such as: - larger second picture when you click on one - ability to have add ons when you click on a PACK such as a bunch of different colour cup sleeves but the key point is that they have to PAY for the add ons, I also want pictures. SO if you bought a shirt for example 10$ and wanted to add a sticker (2$) and toy (4$) your total is 14$. They need to have pictures beside them as well. similar to this [login to view URL] but not a popup, I need the ability to have add ons and pictures besdie them right within the "add to cart" window once you click on a pack. I will also require the bottom of my store to look like the bottom of this store: [login to view URL] we will also need to add each other on skype