From personal experience, if you're looking to mix/mash then Traktor/FL Studio are good.
However, if you are just looking into song covers then I did a quick google search on what will be best for you.
"AutoTune, Melodyne, Waves Tune, etc" seem to be the popular options but they also state you need a "good voice, a good mic, a good preamp, a good sounding room, followed by proper treatment(EQ, compression, effects)" - Just a heads up.
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