The problem here is that this usage of "like" is very common in English, but has no exact equivalent in French. It is mostly heard, rather than read, because it expresses something different according to the oral context.
I believe that "It's like two miles from here" is slightly different from "It's about two miles from here". In the first sentence, depending on the tone, "like" can be a form of emphasis on the distance, or also insist on the fact that the speaker doesn't exactly know the latter, making it less trustworthy than an "about" approximation.
So, depending on the context:
C'est à environ 2 km d'ici (simple approximation)
Ça/cela doit être à 2 km d'ici
Notice the use of the verb "devoir". If you pronounce this last sentence with a neutral tone, it is just an oral form of approximation; but with an exclamation mark, and with the according tone, it expresses emphasis on the distance ("It's too far away, it's like two miles from here!"). Further precision: you would say "ça doit...", but write "cela doit...".
As for the second sentence, it is more simple to translate.
Ce plat était délicieux, j'ai dû manger 2 kilos de viande !
This is a very common form, and in my opinion it is the best way to translate "like" in this context, as the verb "devoir" here expresses doubt on the ingested quantity in a sarcastic way, as "like" does in the original sentence.
In case you wonder, I am French, so I can tell you these are everyday usages ;-)