Also, it's a common misconception that large tech companies like Google and Meta sell your data. They don't. The data is what makes the company valuable - they're not going to give away their competitive advantage. Instead, advertisers can target people based on the data. The advertisers never actually see the data nor exactly who their ads are reaching (it's just aggregate anonymized data).
On Google and Facebook, even individuals can use the same tools that large advertisers use to list their ads, and see exactly what they see.