Hello Hira ::::: Hmmmm. I am skeptical of your coin. Look at the one above from Roma Numismatics. It is a ***gorgeous*** coin, with plenty of detail, clear inscriptions, sharp features, and good overall quality. Your coin, in comparison, looks very crude.
Based on the overall appearance of your coin, I think it is not genuine, but a low-quality copy.
Here is Roma's description of the coin pictured above:
Price realized: 850 GBP (Approx. 1,236 USD / 1,133 EUR / 1,229 CHF)
Kushan Empire, Kanishka I AV Dinar. Circa AD 127/8-152. Kanishka standing facing, head left, flames on shoulder, sacrificing over altar and holding goad and sceptre / Siva, nimbate, standing facing, head left, pouring water from flask and holding vajra (thunderbolt), trident, and goat; tamgha to left. MK 37. 8.02g, 18mm, 12h. Near Extremely Fine. Some earthen deposits. Estimate: 500 GBP