Short answer - It doesn't work like that, it's directly tied to your circumstances.
You tell an insurer or comparison site what insurance you need and your & vehicles details and they offer you a price quote. Because different insurers see risks differently these prices can vary wildly and some just don't want some particular risk, like new/young drivers, imports, super cars etc.
There really is no way to pick out a 'cheap' one otherwise, but many new drivers do seem to end up with Admiral for at least a year or so, I've had a few policies with them but they because less useful as I got more driving history and wanted faster cars.
If it's your dads car and he's still the main driver with you just wanting the occasional use of it, you could possibly be added as a second driver to his insurance, but you need to be honest about who is doing the main driving.