Hi Plek Trum,
I'm a TEFL teacher and I will be moving abroad to work soon.
The majority of jobs require a CELTA or Trinity qualification. I completed the CELTA, it is not easy, but it definitely does qualify you to work for most of the teaching jobs here and abroad. (it involves a lot of teaching practice)
You can do a intensive 4 week course, or a part time year course.
A DELTA is the next step up from the CELTA, and this will allow you to command a slightly higher salary and opens more doors for work.
If you google "tefl jobs" or "esl jobs", you will see the CELTA is generally a requirement "minimum".
All the best,
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