You can find a Darktable teacher, and I did. He is a professional photographer, but I disagree with that particular teacher's style in photography - especially the rejection of strong edits even if they do work as creative reinterpretations of the scene.
You can find a photography teacher with good taste in composition, with recognition that both ultra-constrained and creative edits have their place (and I did find such a teacher), but that teacher will inevitably use Lightroom. That teacher recognizes what needs to be edited, recognizes that Darktable has the right to exist, but will explain the needed changes using Lightroom tool names.
It's now your job to translate - and, importantly, translate the visual effect achieved, not the slider name. This requires seeing the intended effect. This requires doing it in Lightroom first and then trying to make Darktable output look the same.
For example, the teacher asked for a high-key edit and told me to raise the whites. In Lightroom, this keeps contrast high near the top of the tonal range, right until it abruptly becomes zero because of clipping. That "high contrast followed by clipping" behavior is exactly what the requested high-key edit needed.
But your teacher will never describe it in those contrast-related terms. Before translating the instruction into Darktable, you first have to discover the visual pattern yourself that the Lightroom slider is producing.
And the correct translation, if you use the "sigmoid" tonemapper, is the "target white" control, which the official documentation marks as "don’t touch". You need to set it to 130% via right-clicking to override the soft limit of 100%. Very non-obvious, not mentioned in the Darktable course that I went through, but the photography teacher then accepted the edit.
In summary, the requirement to learn Lightroom in advance just to understand the photography teacher is the real trap here.