The "Proshika Shabda" carries a formal tone. You would not use it for a friend teaching you to cook. Here is a breakdown of when to use it:
Here is where the specific keyword "Proshika Shabda" becomes fascinating. While "Proshak" (প্রশিক্ষক) refers to a male trainer, is the standard feminine form. However, in colloquial Bengali, "Proshika" is sometimes used incorrectly as a gender-neutral term. Grammatically: proshika shabda