If this all feels a bit complex and uncertain, then don’t worry, it’s not you!
Measuring the exact effect of advertising is something that eludes even the biggest companies in the world.
Our advice is to prioritise those Reach metrics, because they are a clear indicator that your ads are being seen by a lot of people. And then, if you have the right ads, and some ongoing advertising budget, you should be able to trust that the process is having a positive effect, even if you cannot see all of it in the data.