Os Commerce Website : Secure it, Made Back up, Learning

Hello, I have an os commerce website. Website is finished but I want it to be securized and running perfectly (perhaps due to fail of security, virus and related issues). I need your knowledge to learn some task i want to realize by myself. Then, I made a proposition of work to made there but i am opened to another solution if you think something is better and more efficient. I want an invoice to attest our work and you have to detail me which action you have made exactly (example : row 45 deleted in file, … ) For reason of confidentiality i don’t want you use name of my website to said you have worked for it. You don’t have to copy any image/logo or any representation of my website. I need : to see it purged from virus and related issues - furthermore, you have to perfectly secure it by correction of fail of security that allow thief to work - you have to detail me which actions you have made exactly (made me a file with line purged for example… if i can open it without risk of contamination !…) - datas don’t have to be deleted you have to learn me how to search by myself any intrusion / virus and related issue. AND If some tools exists please give me informations to understand how to use them - i have a preference for automatic / controls / purge of virus and related issues but keep contrôle by myself if necessary. Important : template of website must be kept and no bugs have to be added please, no regressions on running of website - if something is broken, you have to repair it. once all securized please help me to understand how to made a back-up / restoration of my website when i want (data and structure) you have to help me how to transfert structure of my securized website to another domain (without datas) and help me to understand where i can change logo, banner… if you have recommandations about evolution / migration of my os commerce website to another system, more securized, please tell me. Furthermore I have a preference for update available to secure my website but i need your help to learn to made it myself. This project is not urgent. Perhaps we can solve one task by week and you can work on other project in same time. Don’t hesitate to ask if any questions. Bests Regards.