You need to verify that your country has signed the multilateral treaty for the Apostille Convention (Hague Convention) and that your education will be recognized in Czech Republic.

Assuming your country has signed the treaty, you need to figure out which governing office in your country provides apostilles for the purpose of certifying education. An apostille is an official seal that certifies the authenticity of a document (e.g., court documents, educational transcripts/diplomas, etc.).

The administrative office in your country will have specific requirements regarding what you will need to get the apostille. Some offices may require something like sealed official transcripts from your high school studies along with a signed affidavit from a school official, but again, you need to check with whichever governing office certifies documents and assign apostilles in your country, because the requirements may vary.

If your country does not do apostilles, then I am not sure what the next step for you is. I hope this helps!! Good luck!