Can someone please tell me the easiest way, step by step, to find the indefinite integral of a problem like ∫ 2 𝑑𝑥

Ask yourself, What did I start with so that the derivative of "something" is 2

how about y = 2x ???
if y = 2x, then dy/dx = 2 , so
∫ 2 dx = 2x + c , I assume you know why we have to add the constant of c