Hello Experts,

I intend to apply for a UK Tourist Visa (First Time). I want to know, does my hotel reservation have to cover the whole duration of my stay (3 weeks) or can it be less? I ask this because I do not intend to stay in a hotel throughout my whole stay.

If your application says you would be staying in a hotel then yes your reservation should cover your whole stay. Don't complicate things by reserving a few days then saying you would stay somewhere else a few days.
You can reserve for how long you would be staying in the hotel,and write in your visa application that you would be staying in UK for that same period of time ( preferably 2 weeks ). Then later go where you wanna go to.
Or reserve 3 week,stay as long as you want to,cancel and collect your change ( you might pay a token for cancellation ).

YES.

When you get here, you can inform the hotel that you are spending a couple of days and get the refund back but they charge you something.

Good luck

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