A ready-made example to start with: the guitar is pushed back, the others stand in front. Press Play and switch “How it was” on and off: you can hear the guitar step back. Then turn its “Reverb”, “Top end” and “Loudness”.
Depth of stage0% → 71%Guitar: distance71%
The dot is a source. The higher it stands on the stage, the further away it sounds.
source: smaller - quieter or farther, paler - dullerreverb