Vermaji

You can do this with plain html with a little JavaScript. You also need a automation Platform (likeFred said: make.com or zapier.com) to communicate between Ninox and your website (to hide credentials)

Structure of the html page would be like:

- using a fetch command to get all the items you sell

- make a page (or table) with this data

- buttons to 'buy" the items you want or place them in a "cart"

- "order" button to place the order and send the ordered items to Ninox

To make a page like this, ChatGPT is a very good helper....

If you also want to deal with payments, I would consider to use a third party payment service provider or an E-commerce store.

I had a WebApp built by Scott Dredge that updates fields in the Ninox main DB by engineers in the field.  Essentially, they add serial numbers and other info via their mobile phones, tablet or laptop via the App.  Works a treat.  Only thing you need to consider is API call limitations of your subscription.

Here is a link:  Custom project management app case study | Thorn Creative