Shopify Website Development - Tweaks to website

Hi there, I am looking for some changes to my Shopify website (see attached file for detailed work required). In summary it is to enable some of the the navigation menu options to scroll to a section on the Home Page (instead of the top of the page) and also to change some images for tablet/mobile views so that they are different to the ones shown on the desktop view. The website has been built in the Refresh theme. Looking forward to working with you. Warm regards, Justin.