I can do following edits on you voice recording
- Remove constant ambient noise like fan/ac sound(cannot remove loud bang/horn like sounds that overpower you voice)
- Cut/trim awkward and long pauses
- Adjust uneven voice volume(depends on the quality of recording)
- Add simple effects like reverb/echo, deeper voice, etc
Note: the amount of fixing I can do is entirely dependent on the quality of recording, if the voice is not clear at all, I can't save it.