Tax settlement after selling the stocks in general account.

How to settle tax after selling the stocks under general account (not the specified account where brokerage take care of taxes for you) of brokerage account? If the stocks are received as reward in general account in different time at different rate, how to calculate, report and settle capital gain tax after sell? I tried searching answers to these questions but found completely different answers every time. It will be great help if someone could explain the process of tax settlement.
Thank you for taking time to go through my question.

by Wabi-Sabi97