If it's an audio CD, then you will need an audio program that can extract songs from the CD to your computer. The initial step should be converting these to WAV files. Then after cd extraction, convert such files to whichever format you think would be prefered. mp3 is the most common, but aac (m4a) or any of the compressed lossless formats such as monkey (ape), apple lossless, FLAC, etc. Lossless formats are the same in quality to the originals but compressed (about 65% of original size.) Whereas mp3, aac, ogg vorbis, wma, are lossy formats in that they throw away information in order to help reduce the file size. This generally starts by getting rid of frequencies above 15 KHz. And other techniques are used to reduce size.

Qualities of mp3 or aac 192 kbps or higher are good quality .... anywhere up to 320 kbps.

To share your files, see How to Share Folders (click on link)