Depends on one’s mother tongue, one’s ability to learn languages in general (some have it easy, others less so),and possibly also one’s age. For me, being Dutch (neighbor of Germany, and speaking a language from the same group of languages), it was not too hard, when I was taught it in school. It really depends. - Recently I came upon a list of languages and the difficulty speakers of certain languages had with certain other languages (say, Thai have difficulty with Spanish, but French have less difficulty with Spanish). I’ll have a look if I can find it.