The wave file you posted clips out at certain points. I don't know what you did to the parts that clipped, but try not to let that happen. You can tell that the audio is clipping if it goes above or below the track's visual boundaries. Most DAWs have a little red light on the dB meter that lights up if the audio clips while playing. You can also listen for distortion.
Towards the end, the voice sounds a bit tinny. That's good if you have a guitar or other instrument in the mid-low frequency range that you cut out, because it allows the guitar to take its place in the mix. You can also EQ the vocal range that you like out of the guitar, so that they both sit in their own little spaces.
If you don't have another instrument in there, don't make it sound tinny, unless that's what you want.
On that note, almost all of audio engineering is arbitrary. It's about tweaking and listening for what you want to hear. It's not about searching for magic numbers. There is no "right" way to do EQ.
You should actually try the tutorial I sent you before posting again. Try using REAPER (it's free but nags you until you pay) or some other DAW with realtime EQ feedback, rather than Audacity, which doesn't. Select your audio, turn looping on, start playing, and tweak the EQ. When sweeping, you will suddenly come across a frequency band that becomes very loud. If you like that part of the audio, keep it or boost it a bit; if you don't like it, cut it. Again, it's an arbitrary process.