This might sound like a silly question, but it actually isn’t.
It might seem counterintuitive to teach English in a country which speaks English as their first language, but teaching English in the UK, the USA, Canada, Australia, New Zealand and South Africa is big business.
In these countries you won’t be teaching the English speakers of that country, but the learners of other nationalities who come to that country to study, work or learn English.
So while it’s unlikely you will find a job teaching English in a mainstream school, you will very easily find a job in a language centre or university.
Read more: Can I Teach English in an English-speaking Country?