If you want to do voice acting, I first suggest downloading Audacity.
It's a great freeware program for recording, and it's simple as well. If the only mic you have is the one built into your laptop, you're gonna need to clean it up a lot in audacity.
Make sure you have quiet surroundings when you record, move away from the mic to breathe, and if not, then filter it out. Filter out all unnecessary sounds so that it's just your voice.
Play around with the volume controls to make sure that your voice can be heard, but that it's not too loud.