Rewiring small cabin and thinking 30 amp and smaller gauge wire is undersize. How do I calculate correct amperage for breaker. Thinking data (wattage) shold be on back of stove. Then what is the calculation, e.g. watts divided by 80% of breaker size?

Understand that: 50-amp = 6 gauge, 40-amp = 8 gauge, 30-amp = 10 gauge.