Wix website optimisation SEO

My business supplies projects, resources and consumables such as architecture model kits, modelling foam, balsa wood, solar and CO2 cars, ukulele and jewellery box kits and STEM based projects to high schools in Australia. I have built my Wix website and have completed some of the SEO optimisation tasks but am short on time and would like to quickly complete anything else that may help improve SEO on google etc. I also I have a few problems when the site is viewed on mobile, iPad and iPhone. I am looking for a WIX website expert that can perform these services and give a general overview of the improvement that can be made. Thanks Dale