If you want to be a tour guide or tour leader in Thailand, you don't have a certificate to speak a little Thai.

As a foreign tour guide, if you have not obtained a tour guide card and are proficient in foreign languages, you can apply for a temporary tour guide card to take a tour group. To be a full-time tour guide, you must obtain a tour guide card.

Being a tour guide means taking a tour group abroad, and you need a tour guide card. The prerequisite for obtaining (or applying for) a tourist guide card is to have a tourist guide card.

Therefore, it's better to take the tour guide card first, depending on whether you want to be a ground tour guide or a full-time tour guide, and decide the language of the tour guide card. If you want to be a tour guide and take a tour group abroad, you need to take a tour guide card.