Currently, if anyone chooses USD as a payment option for my Shopify website. On the checkout page, they see the amount converted to INR. What is the way that the user can choose from an option of currencies and pay in that only with the amount being converted into INR. I am in India and we can use apps and plugins available to India.
I am not an expert on payment methods, but you may refer to Shopify links and find useful payment gateways available in India: https://www.shopify.in/payment-gateways.
While once you set up multiple payment ways, you may also auto display local currencies and payments upon checking out. When the currency is changed, it adds a parameter to the URL, for example, exampleshop.com?cur=USD, or exampleshop.com?cur=INR. IP geolocation tools can detect your visitors' location using IPs and auto direct visitors based on their locations. If your visitor is in India, and he goes to exampleshop.com, instead of having your visitors selecting the currency, it will redirect the visitor to exampleshop.com?cur=INR immediately showing Indian Rupees and upon payments. For example, you may checkGeo Targetly and its Geo Redirect tool. You can simply set up redirecting rules within a few steps. No code is required. In this way, it engages with customers and increase customer conversion rates.
Hope it helps!