What technologies to choose for web/desktop app?

Question

RESTful API

Hello, I am not at all a programmer by my main profession, but I am familiar and interested in this area, although I have never gone beyond the frontend on the web.
The task is to create an application for calculations (calculations are designed for a narrow audience of "their own") and ideally it should be possible to use it as:
1) Web application
2) Desktop application table)
Mobile version is optional.
The problem is that I don't know what is the best way to implement this. I know that it is possible to synchronize requests via REST by binding to inputs and labels, and as I understand it, you need to create two separate interfaces, and somewhere here my knowledge about this ends)
Please tell me in which direction to look, what to read, are there any other options for implementing something like this? and please, without suggestions, create what you need in WordPress, etc. because I would like to understand how it all works. From what I can use: C++(qt), Python, JS

Answer 1

If the application is standalone, does not interact with the Internet during launch and operation: Archive with html / js / css files and then launch the index.html file through the browser (via the "shortcut" or directly: through explorer, etc.) pack any installer.
Weight - small (5-7mb), calculation functionality - working.
Else: nwjs.io . The weight of the "empty" application is from 85Mb.

Answer 2

Electron or Qt for example.

Answer 3

Pay attention to NWjs

Answer 4

For quick MVP prototyping, you can use Laravel + Mysql on the web ( rest api requests are supported out of the box, limit on throttle requests, don't forget to create api keys for users ), for desktop, use QT