What's the difference between "à" "en" and "dans"?

[blazing breach]

Salut! What's the difference between "à" "en" "au" and "dans"? And when do you use them?

[fluid mulch]

Oh my goodness that is such a broad question (:
You should read this LawlessFrench article, read the entries that you want to know, and then come back here if you have follow up questions.