I believe that it is a good idea to learn kotlin first, since in some senses it is simpler than Java and there are some things to unlearn at least if you use “old” Java (before java 8). But Kotlin is new so there is not much educational content for it.
Of course if one had bad English, it is a problem since there is almost no localized content for Kotlin. So if one asks what language to learn first, I say learn English.