Calque is a way of borrowing words from another language. In this process, there's a direct translation of the elements of a word into the borrowing language.
Is calque equal to literal translation?
No. Calquing is the use of literal translation of a word or phrase to refer to the same thing that word or phrase refers to. So literal translation alone wouldn't be a calque.
No. Literal translation refers to full sentences or texts while calque refers to a translation unit (word or multi-word expression). You can do literal translation without ever using a single calque, and you can use a calque of a certain word in a non-literal translation.