Adobe premiere, how do i link two audio clips and one video clip for the purposes of the razor tool?
Even though Michael Tiemanns answer is technically correct, it seems overly complicated given the description of your problem, as nested sequences may cause other problems and inconveniences down the road. So here are two other options that might help you:

Grouping

Select the three tracks you want to edit, then right-click → group (or press CTRL + G). The grouped clips will all be selected when you click on one of them. Then you can press CTRL + K to cut all clips in the group at the position of your playhead. The problem with this method is that the cut clips will still be grouped together, so if you select one of them, they will all be selected and moved simultaneously. The next option will be more convenient for your workflow:

Track locks

Click on the lock symbol on the left side of the timeline on the track that holds your background music. This will completely lock all clips on the track, preventing you from accidentally cutting or moving them.