Learn Portuguese (Portugal): Não é assim.

In Portuguese, you usually do not need to use subject pronouns (like 'I', 'you', or 'it') because the verb form already shows what you are talking about. Here, the verb é (is) implies 'it is', so a separate word for 'it' is simply dropped.

Why does não come before the verb?

In Portuguese, negative words like não (no or not) almost always go right before the verb they are negating. So, instead of saying 'it is not', the structure is literally 'not is' (não é).

Does assim literally mean 'like this'?

Yes! Assim is a very common word that means 'like this', 'like that', 'this way', or 'so'. Instead of using separate words for 'like' and 'this', Portuguese uses this single word to describe how something is done or how it is.