make vocals sound good and mixing to instrumentals?

[Takayuki]

Hello,
So I was wondering I hear some recording and they are ok. Not good, not bad. Can carry a tune. But when I hear the final after editing it sounds super good. they have crisp control of their voice that I didnt hear during the recording.
How is that done?
If it was professional I could understand. But sounds so much more crisp and good to mines. Im not a good singer, not that bad either.
I tried to read many site that explain the process. compression, and a bunch of terms I have no idea what they mean, then I search for what each word means, and end up getting more confusses because when looking up what it means I find more words and i goes on. haha

So I guess I will say what i want to do.
I want to just sing cover songs (all or most japanese songs)
So I have the instrumentals and want to record vocals.

I use reaper to record to my computer using a Tascam US-122L interface, and a mic.

Then if I need to edit, change pitch, add reverb (the only few words that I know the definition to) I do it in Audition.
Then I mix paste my vocals to the instrumentals.

Im sure many are laughing at me, and praying that I do more than just record and slap them together...but thats all I do.

So what are somethings I can do to make it sounds better (not make my singing skills better, but make it sound crisp, and like the vocals is a part of the song and not just laying ontop of the insturmental).
Please bare in mind that I know close to nothing about this.

I have a song I recorded that I can PM to you if you want to hear and see if you can help me.

Thanks