An ordinary audio CD contains stereo tracks that are recorded at 44.1KHz sampling rate and 16 bits.
Either record the tape deck from its stereo outs or record all four tracks down to stereo.
With Adobe Audition I record a 4-track tape as a 4-track computer session, then mix down to stereo. AA allows me to tell it to record at 44.1KHz, and the default bitdepth is 32, so I convert to 16 bit, and save it to a folder to burn to CD.