I think you'll know when you feel it... You may never feel your dominant side... until that moment you meet a person who naturally submits to you.

And, it's a different question than the purely play side of topping and bottoming. Not all tops are dominant, not all bottoms are submissive. I know that sounds strange, but some subs enjoy giving pain under orders from their dom/me (often to third parties.) And some dominants enjoy sensation play you ordinarily think of as masochistic.

Don't let labels put limits on your explorations.

So you question isn't really all that confusing... but maybe the answer is.

And even then, if one would find that dominating is not his thing, can a person learn to enjoy it?
I know a number of submissive women married to submissive men... and they'll gladly top them out of love... after all... that's what subs do... they give. No doubt some will be able to chime in on how enjoyable (or not) they find it...