You can download the manual for this device here
. The downloaded file is called "ad-rw900.pdf" and should be found in your download directory.
Locate and open the file (Adobe Reader) and review page 31. Here you'll find the details to go about recording a CD from the source you've selected with the "Input Select" button. When recording to a CD-R or CD-RW with a cassette TAPE (or LINE IN or PHONO) as the source, you must manually set the recording level as directed in step 5 on page 32. Check the blank recording media. The device is ONLY capable of recording on "CD-R" and rewritable "CD-RW" blanks (these are very different from DVDs of any type). The CD-R type will likely enjoy wider compatibility (than CD-RW types) when played back on a different (car or other) CD player.
I hope this helps & good luck!