Add a translation dictionary to Apple's in-build Dictionary App

Hey folks!

** I did not find the right community to ask this question, maybe you can guide me? **

I am coping with something annoying for a long time. Since english is not my mother tongue and I am doing studies in that language, I spend a lot of time searching for translations. Up to now, I am always switching between an internet translator tool and my document.

So, has anyone an idea about how to add a "translation dictionary to Apple's in-build Dictionary App"? I found other topic about this kind of question on the internet, but none of them is working. Either the website from which we are suppose to download the dictionary is expired or the downloading doesn't work (or maybe I am not able to follow the steps?).

Maybe someone knows a little bit more about it?

PS: In my case it would be a french-english dictionary

Thanks a lot for your help!

Valérian