Too many is for your countable nouns, basically everything else!
I have too many phones! Which one is ringing!
They have too many children, how do they remember their names?
We have too many reports to do for tomorrow.
I have too few friends, I really need more.
There are too few interviewees, so I can’t make a decision.
Excellent work. Next we have my quick interactive video, so you can practice 📹