How essential are Maxwell’s equations for understanding Yang–Mills theory? [closed]

I am trying to understand the precise relationship between Maxwell’s equations and Yang–Mills theory.

My present understanding is that electromagnetism can be formulated as an Abelian $(U(1))$ gauge theory, while Yang–Mills theory generalizes the gauge-field framework to non-Abelian groups.

How important is a strong command of Maxwell’s equations for understanding that relationship? In particular:

$1$. Which aspects of Maxwell’s theory are indispensable—the field equations themselves, the four-potential and gauge invariance, the Lagrangian/action formulation, or differential-form notation?

$2$. In what precise sense do Maxwell’s equations appear as the Abelian case or limit of the Yang–Mills equations?

$3$. What new mathematical or physical feature introduced by a non-Abelian gauge group marks the decisive departure from electromagnetism?

I am asking about the conceptual and mathematical dependency between the two theories, rather than merely which subject should be studied first.