Music theory is two notations and a lot of naming, and people usually stall in the gap between what they read and what they play. The names are not arbitrary: a chord is a set of distances, and its name is a description of them. The block below edits one chord from either notation and tells you what you have built — and plays it, because the difference between a major and a minor third is not something to take on trust.
Click the keys or the staff. The chord is named from its intervals, and the slash tells you which note is lowest.
That is C. The name is not a fact about these keys: it is a description of the gaps, which is why moving the whole shape up a key renames it and changes nothing about how it sounds.
You describe the goal in your own words and it asks questions back until the plan is one you would actually follow. These are the shapes that goal usually takes.
Not a fixed syllabus — the plan is built around your goal and cuts what does not serve it. These are the topics it draws from, and whatever you get wrong comes back until it stops coming back.
The mechanics are the same whatever the subject — a slider is a slider whether it is moving a coefficient or a rate of return. What changes is what it is a slider for.
Or see how it works and what it costs.