Dear Sir,
Here are my replies to your queries:
1) Regarding Income: As you mentioned that your course price is $97, so in that case whenever anybody is purchasing any course from your website will pay $97 and it implicitly means that you are selling that course to that customer at $97 and your income will be $97.
If a customer is paying $97 for your course, it means that will be your income. And the amount deducted by either paypal or the website as commission will be your expenses. Meaning thereby your net income will be $ 92 ($97-$5).
2) GST Return Filing: For filing the GST return you are not required to take the exchange rate of the future date. As your income will accrue on the date when the product is sold and payment is received by the website or paypal. So, accordingly you have to consider the exchange rate of the day when the product is sold irrespective of the fact that when you are receiving the actual payments.
3) GST : In case the courses are purchased by any customer in India in that case it will not be considered as export and you are required to pay the GST on the same by calculating the amount of GST by considering $97 as inclusive of GST.
Hope your all the queries are resolved.
Let me know if you have any other query!
Thanks and Regards
Divya Chugh