Adding junction box help

Junction box question

Id like to mount a junction box on here to run some mc cable to put an outlet further down the wall. There’s mc fed into that recessed box and caps here. Is there a proper way to feed the cable into the new box if I was to mount it over the hole? Thanks!

Junction box question

Id like to mount a junction box on here to run some mc cable to put an outlet further down the wall. There’s mc fed into that recessed box and caps here. Is there a proper way to feed the cable into the new box if I was to mount it over the hole? Thanks!