Use Garageband as that will do the job.
Honestly there is no such thing as professional or non-professional software in terms of recording quality as a sample is a sample is a sample. Garageband is just fine for voice recording so long as your USB Mic is reasonable. Even if it is less-than-perfect, Mic positioning and levels are probably more important than buying new gear.
You set the Recording quality like Bit Depth in GB’s Prefs. Honestly, if it is just a voice recording 16/44 is more than plenty. Set the Levels so they obey this and you are probably right.
Aim for clarity and hire in a Mix Engineer with experience in voice work if at all unsure as it is easy to over-process (butcher) a voice track.
