Can a paper be presented by two presenters in a conference
Registration and presentation of a paper are two somewhat separate issues. Normally, presenters at a conference must register, but there is no rule that says only one author of a paper can register for a given conference.

In general, however, papers normally have only one presenter, as the logistics of a conference normally work against having multiple speakers for a single presentation. (The presentation time is not that long, transferring a microphone between speakers, ensuring proper "flow" of the talk across the change in presenters, and so on, all tend to work against the idea of multiple presenters for a given paper.)