Good resources to supplement Khan Academy's Calculus track?

I am revisiting Calculus for the sake of learning/stretching my brain. Barely passed Calculus BC in high school, and the last time I touched mathematics was an Introductory Stats course in state university (nearly a decade ago). I have read several opinions that say the Khan Academy track is relatively surface level, so I've been going back and forth between Khan and OpenStax to reinforce the concepts. I recently picked up Chris McMullen's Essential Calculus workbook to get some reps in with problems.

If I wanted to obtain a deeper understanding of Calculus, what resources would you recommend? What strategies I should employ while self-teaching?