Why does God in the bible, churches etc... only warns us about Satan when there are more evil devils than satan?

I used to believe that satan was the only devil because I never heard of any name from hell besides satan

I was never a religious person but as a kid growing up going to church the only devil we were taught about was satan and about how evil he is amd the story between God and satan

To my surprise now that I'm 28 years old I'm only learning now that satan is not the only one that was cast out of heaven and there are demons more evil that satan that Christians should avoid and I only learned this by doing my own research

Now my question is why are we not taught about this? Why do people only warn us about satan and only talk about satan when referring to hell?

Why does God in the bible, churches etc... only warns us about Satan when there are more evil devils than satan?
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