A lot of theatrical stage lighting design is based on and has evolved from Stanley MxCandless book A Method Of Lighting The Stage  https://archive.org/details/methodoflighting00mcca

This lighting design method provides Visibility, Selective Focus, Modelling and Mood.

If you look at Choosing Lighting Positions in Lighting The Amateur Stage by Francis Reid https://www.theatrecrafts.com/archive/documents/lighting_the_amateur_stage_1.pdf you will see that lighting straight on from the front restricts your lighting design.
This booklet and the second volume https://www.theatrecrafts.com/archive/documents/lighting_the_amateur_stage_2.pdf provide an excellent summary of stage lighting for amateur theatres and schools.

Theatre 476: Stage Lighting
This is Professor Paul Collins website at Central Michigan University http://thtr382.weebly.com/
There are a lot of photos and videos in each section to help explain and visualise each section.
Elements of Light
Functions Of Stage Lighting
     Given Circumstances
Lighting Equipment
     Dimming & Control
Lighting Design Process and Paperwork
     Research & Inspiration
     Color Map
     Systems and Specials
     Cue Sheet
     The Light Plot

Page Updated 15 February 2022