GST

Dealing with ITC loss can be such a pain. Here’s a simple tip: make it a habit to check your suppliers' GSTIN every month. Using a tool like ExpressGST can really help keep your 2B data in check. Also, if you include ‘proof of filing’ in your vendor contracts, it gives you some solid protection. A lot of successful small businesses do this as a quick 20-minute weekly task. It's really not much to ask, and it helps keep your cash flow safe from any GST mismatches.

You only need to register for GST if you are earning more than 20 lakh rupees. Since you are making less money than 20 lakhs, you do not need to register for GST.

For your online store, even if your revenue is minimal, you may need to register for GST in India. If your annual turnover is below Rs. 20 lakh (In some states its Rs. 10 lakh ), you are not required to register for GST.
But as you mention, you are involved in both interstate and foreign transactions, you need to register for GST no matter how much business you do.
With your expected minimal revenue, registering as an individual (sole proprietor) with a GST number is advisable for simplicity and compliance with e-commerce requirements.
It’s advisable to consult a GST specialist who can provide personalized guidance based on your specific situation.