how can i set my prompt template to be

It will depend on which LLM are you using

If the llm is capapble of responding in your preferred language or not.

You can always find what prompts your engine is using using this: https://docs.llamaindex.ai/en/stable/module_guides/models/prompts/usage_pattern/?h=prompt+upda#accessing-prompts


and updating prompt to include your instruction as well: https://docs.llamaindex.ai/en/stable/module_guides/models/prompts/usage_pattern/?h=prompt+upda#updating-prompts