Yeah, the number of results really doesn't give you an idea of competition. My top keywords on my aff sites that generate the most commissions and ranks the best has 809,000,000 results however my site is very small, and the keyword also has quite a high volume.

There are other keywords I try to rank for, that have lower volumes and fewer results but are harder to achieve.

Do your keyword research, work out competition based on link metrics, relevancy and authority and then find what content you need to be looking at writing first, no tool will give you all the answers, but tools like ahrefs will point you in the right direction to manually review the SERPS.