Which finger for each number
Left pinky 1, ring 2, middle 3, index 4 and 5. Right index 6 and 7, middle 8, ring 9, pinky 0. Reach up from the home row and come straight back.
This typing test mixes numbers from the top row into normal words, the way they appear in emails, invoices and reports.
Around 40 wpm is average. 60 wpm or more is good for most jobs, and 80 wpm or more is fast. Keep accuracy above 95%.
For numbers inside text, use the number row. For long columns of figures, the numpad is faster if your keyboard has one.