Hey @Ankur Mittal22,
Apologies for the delay in response. Trailing Stop Loss and GTT order feature is not there currently in our platform.
To reverse a position, you will need to click on the Reverse Position button which is popped up when you place an order.

For Example: If you have placed a Sell Order for Punjab National Bank, you wish to change it to Buy, you can do so by clicking on the Reverse Position as displayed in the image above. A pop-up would appear for confirmation of the same. The order would be reversed to a Buy Order once you click on Confirm.
Hope this addresses your query!