If you want to know if a Company is running Ads, The first step is to check, if they are running Facebook Ads.
Here is how you know if someone is running Ads on Facebook
Visit https://www.facebook.com/ads/library/
This is Public because Facebook was mandated to share this to everyone.
You can filter by countries and search for specific keywords too
Things you can Do
Search for Keywords around your business to understand what kind of ads are being run for similar businesses.
Keep an Eye on Your competitors by checking the kind of Ads they run on Facebook
Filter by Country, You can filter the Ads by any country and checkout what Ads a company is running on different countries
How I use Facebook Ad Library
I have a product called tapthe.link . It’s a deep linking tool which can skip Facebook Browsers and take users directly to apps. Super useful if you are running Ads to your Amazon or Spotify.
I stalk some big creators/ media companies and cold email them to use my product and give them a discount.