Improve and customize our Shopify Website

Hi
We have this website
www.unairdantan.com
1.We need to set up this app "Product Personalizer". We already set up the basic app but we need to add the Price Per Option part and set up all products to personalize (4 products to set up)
2. We need to modify the header of the site, reduce the size of header and customize the menu bar so that all elements of menu appear in the header and not by clicking on it only
3. We want to customize the button "summer shop" and place it in the center of the main image, and reduce main iamge size