The idea sounds good. But I am not sure how much help you can get on the questions you asked. Its your project so you need to define the most of it.
But since it is a Browser it will a client application (possible Winforms or WPF).
Something like this: Web Browser in C#[^]
And you will have to have this application capable enough to be able to learn and act on voice commands.
Something like this: Speech Recognition[^]
Perhaps the combination of both these projects itself is your complete project. But I thought I should atleast point you in right direction so that you know that it is totally feasible project.
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