The sentence in its entirety goes as follows:
When I was your age I could play the role of Yang Zongbao!
I know translations are not a hundred percent, but I use it in my current routine to make sure I am not missing grammatical functions my mind has not yet got a grasp on. In this case, I am wondering where the potential comes from. Why is it that the speaker did not play Yang Zongba, but rather, cold have played?
票戏 = amateur performance
去 = to play (a role)
The key seems to be 还. Why is 还 here a potential, rather than just used for emphasis?