Question about Front derailleur?

Question about front derailleur. I was trying to adjust my front mech and adjusting the cable tension and it seems that I have screwed the barrel adjust near the shifter all the way out and now the barrel adjuster doesn't work and doesn't adjust the cable tension.

I looked online for research and think I've found the answer which is this.
"hould be easy to fix. To make getting it back in easier slacken off (undo) cable at derailleur to take all tension off cable. Slide outer housing out of barrel adjuster at shifter. The barrel should now be easier to align back up with housing to screw it back in.

Screw barrel all the way in then unscrew about 2 turns. Insert outer cable to barrel (and cable stops on frame if it has come out). Reconnect cable at derailleur - do not pull too tight (sounds like you already discovered why). Now you can fine adjust using barrel adjuster."

But my question is, I'm unsure how I'm supposed to slacken off or undo the cable tension . Do I unscrew and remove the cable at the derailleur and put it back in after? Tia any help appreciated

Note* The bike is about 4 months old with not a lot of use and I'm fairly new to cycling and am fairly new to gear adjustment.