>>5037
tl;dr - To be safe, ask "Are you British?" instead of "Are you English?" to minimize the risk of unintentionally offending someone.

Also, that British guy who speaks native-level Japanese has his own YouTube channel.
@お喋りじょーじの戯言

https://www.youtube.com/@%E3%81%8A%E5%96%8B%E3%82%8A%E3%81%98%E3%82%87%E3%83%BC%E3%81%98%E3%81%AE%E6%88%AF%E8%A8%80