Idiom for explaining something to someone who clearly knows the topic (probably better than you) [duplicate]

I am looking for an idiom/phrase which would mean that someone is trying to explain something to someone who obviously knows how it's done. It would be like a maths student trying to teach/explain to his maths professor in his university how to do calculus - he clearly knows it better than you!

My language has for example "nie ucz ojca dzieci robić" - that translates as "don't teach a father how to make kids" - is there an equivalent in English?

You don't teach your grandmother how to suck eggs.

A current term is mansplaining. Originally, this meant by a man to a woman, but the Wikipedia article suggests that it can be used more generally.