I think the real question is "Will I be ready"?

With attrition and hiring going the way it is, this is rapidly becoming a 'sooner, not later' issue.

There's a lot more to being a Captain than just flying with your left hand. FOs should take every opportunity to get involved in what their Captain is doing, particularly on the ground...and Captains should see FOs as 'Captains in training' and should make every attempt to involve them in decision making.