Native speakers make mistakes when things sound similar, e.g. effect/affect, then/than, etc. For non-native speakers those are very different words because they have a very distinct meaning in our heads so it’s impossible for us to confuse them.
On the other hand Non-native speakers tend to use the wrong word order, for example using a lot of “of” (House of my friend/My friend’s house) or affirmations that are meant as questions (How you did that?/How did you do that?). This happens because in our native language that’s the way phrases are structured, and internalizing the structure of a language happens long after you have enough vocabulary to communicate.