System migration - need advice choosing new platform

I am a Spanish speaker I will try my best in English I hope I made myself clear enough. During many years I have been working on a spreadsheet (google sheets) for a company, to be used as the main database and management system, where you can find customer info, you can see all the purchases made by that client, you can get a list of clients that need to be reached, you can find the prices list for the products, product information, you can use it to input the orders, print every order and track it until delivery and payment, and the order itself also feeds stock, create an order to refill stock, It is also used to calculate the payment for the salesmen, create statistics and get sales trends, etc. It includes almost everything the client needs, it's pretty cool. Everything created in google sheets. No macros needed so far. The thing is that now the client needs to make the same system but more friendly to be used for non experienced people (almost none IT knowledge, I mean, at all!). I am not sure what platform should I choose to create this system, it will be starting over, but I cannot wait to start working on this new challenge. The good thing is that I have now some knowledge in JS and I am learning also HTML and the tools to develop web pages. Not sure if I can use any of these to work on this project. What do you recommend? Thanks in advance.