"Tú les das muchas cosas."
Translation:You give them many things.
Absolutely,. I hope you reported it, not just told us lot!
Your version clarifies better in the English that "les" is the INDIRECT object, ie TO them.
I am confused: I thought Les was "to read" in second person (tu). What does it mean here?
Leer is the verb to read and lees is 'you read'.
Les is being used here as an indirect object pronoun for 'them'.
tú das - you give
les - to them
muchas cosas - many things