We can't say that mother tongue could be same as native language. You can take my example only. I am from India and I like ICSE syllabus the most.
Explanation:
Native language refers to the language of the area the person grows up in. For example, growing up in the United States, your native language would be English. It's the language used every day everywhere you go by the vast majority of the people there. Mother tongue refers to the language of the family you grew up in.