How to find out on a scale if a company has a pixel (FB or google pixel) or not on their website?

1.) Hey, I would like to get a list of companies (e.g. fb ads agencies) that have a pixel on a website, how can i do this on a scale without doing it one by one?

2.) Does anyone know a software where I can get the leads?

3.) Also how can i find out if they have run ads in the past 90 days without doing it one by one?

Any advice is appreciated