Edit an online store on shopify for my needs

I would like to customize my website to make it more mobile friendly and optimize speed. Smaller currency icon currency to change on all products when selected zoom in function for product gallery sticky header to change width and color on scroll similar to this website: [login to view URL] product layout to be similiar to the following website: [login to view URL] not hard project very easy, have done most of the work. I will send my script and website to the succesfull bidder to edit for me