How should a late-30s skincare beginner approach a basic routine before actives?

[Mia9]

I've finally decided to get serious about a proper skincare routine in my late thirties to address increasing dryness and some early sun damage, but I'm completely confused by the overwhelming number of products and conflicting advice about actives, layering, and whether a ten-step process is necessary or just marketing. I've purchased a gentle cleanser, a vitamin C serum, a moisturizer, and sunscreen, but I'm unsure about the correct order of application, how long to wait between steps, and if I should incorporate a retinol product at night or if that's too aggressive to start with. For those who have developed an effective, no-fuss routine, what are the absolute essential steps and products you wouldn't skip, and how did you introduce new actives without irritating your skin? Is it better to master a basic routine first or to target specific concerns right away with more advanced ingredients?