What technologies to choose technologies for a web project?

Question

JavaScript

Good afternoon friends! The project is simple at the moment: user authorization by mail \ login, then the user is asked a question to which he answers, or a line is given in which he must fill in the gaps. Plus instructions on how to use it, most likely there will be voice acting questions. The next step is implementation for mobile platforms, most likely.
Questions:
1. What technologies to choose for implementation? I know C# (Junior) and they will say that you need to learn ASP.NET Core, Xamarin, etc. But I have a feeling that it will be something like "shoot a cannon at sparrows". It is necessary to find the most optimal technologies ( ease and time of learning, etc. ). It is clear that one cannot do without knowledge of HTML, CSS, JavaScript. But what else? React and React Native? Dart and Flutter?
2. Where can I order the design of such a site - stock exchanges, etc.

Answer 1

1) The project is simple, no react is needed here. Optimal technologies: jquery, html5, css3. For the backend, you can use c#, you can use php. On both, these functionalities are not difficult to implement.
2) fl.ru , weblancer , freelansim There are many more on Google.
I would not recommend voice-over questions, it is not convenient and useless, unless, of course, your site is not for the blind.

Answer 2

Phonegap