Sir without sim slot how can I use my iPhone 4

If this phone does not have a sim card slot, it would be a CDMA phone. The only way you'd be able to use it in India is if there are any CDMA carriers in Hyerabad. You'll need to check with the carriers to see if they can support CDMA.

There are two primary technologies for cellular service - GSM and CDMA. Your phone is clearly CDMA, which is not the dominant band for most of the world. This article explains the difference. What you have to do in order to use the phone in India is find a carrier who supports CDMA. I don't know which if any carriers in India do support CDMA. If none do, you won't be able to use the phone.

CDMA vs. GSM - What's the Difference? | News & Opinion | PCMag.com

This is a list of the major carriers in India. It does not appear they support CDMA, which means you won't be able to use that phone in India:

https://en.wikipedia.org/wiki/List_of_telecom_companies_in_India

You cannot use that phone on a GSM carrier's network. The iPhone 4, when first introduced to Verizon, was for a CDMA only network, and cannot be used anywhere else. That phone will not work for you on a GSM network. If you just purchased it, I would return it for a refund.