Hearing other tracks whilst recording

Ok, this is driving me nuts. To listen to other tracks while recording on one track, say I have 3 instruments tracks, two with recorded midi parts. How do I listen to those two whilst recording. Do I highlight the two tracks? Do I put on the monitoring button on those two tracks? Not long ago all I had to do was highlight and record/enable the recording track. The other two used to just play with nothing being done to them. Thanks, I know really basic, but something’s totally changed and it’s driving me nuts.Thanks guvnuh I’m using cubase 10 in Windows 10 and recording with a first gen axiom 61.

Ok, it seems it must have to do with the direct monitoring feature on my interface.