Understanding VAT on Mileage Expenses

Hello and thank you writing.

I had looked at that HMRC topic last night and couldn’t understand it. I simply need to know whether I need to choose to add the VAT at 20% when adding these mileage expenses. Whether I claim it back or not. At the moment I am putting “noVAT”

It is my own private car which I am using for my business mileage and I reclaim 45p per mile.

Thanks

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