I tried using a Y splitter to split my speaker from only audio to audio and mic because my speaker has one stereo and one mic female. However, when I plug in my headphones into my speaker, nothing works. When I unplug the audio plug, the audio works, and when I unplug my audio plug, my mic works.
I don't understand your last sentence,
"When I unplug the audio plug, the audio works
when I unplug my audio plug, my mic works. "
Which audio plug you have like 6 on your drawing, and I doubt you indented to repeat the same thing twice (or did you mean that everything works if you unplug the earbuds?)
what's your speaker model, earbud model, and which kind of connection are you using, 3.5mm mini-jacks? (ie: stereo or something else) ? Is the microphone on your earbuds or is it a separate device? Usually audio splitters will take 1 source and split it in two, you cant combine stereo audio from two sources into one so that splitter between the earbud and speaker is probably connected the wrong way. Unless I'm misinterpreting what you're trying to do or the kind of splitters you're using.
I don't really understand why your speaker would have 1 microphone input yet no way to transfer that signal back to the PC. Unless it's intended to just output whatever the mics picks up to the speakers in which case it's unlikely to forward it to your PC
You can try this instead assuming your splitters are ONE male mini-jack on one end, towards TWO female minijacks on the other and that both sides are stereo
Edit : I can't make it look all nice but basically one splitter to split the Line out of the PC, and one to split the microphone
PC Line out -> Splitter ----
\--> Speakers <--\
--- Splitter <-- Microphone
PC Mic IN <-------------------------------
This should make it so your mic signals get sent to both your PC and speaker
and your PC sound is sent to both your speaker and headphone
I also don't see why you would connect your speakers to the mic input on the PC.
The green audio output jack would normally be split to connect to both the speakers and headphones if the speakers didn't have their own headphone jack.