I have my gaming headphone plugged into the front two audio ports for audio and microphone, and I have computer speakers plugged into the rear audio out port. Is there any way to output audio to both the front and back at the same time?
Are you talking about "front and back", as in, the ports on the front of your case vs the ports on the rear of your case, or are you talking about "front and back", as in, the jack meant for the "front" speakers and the jack meant for the "rear" speakers ("rear", as in, the rear speakers in a 5.1 setup)?
In the case of the former, both jacks should work simultaneously. If not, some audio control panels will have a setting to "automatically mute the speakers when a headphone is plugged in" or similar. Check for that, and disable it if found. Assuming the latter, there may be a setting in the audio driver control panel to duplicate the sound on both jacks, but probably not. The easiest solution in that case would be to simply use a splitter. Example: https://www.ebay.com/itm/113779503250