Taking the single variable calculus course from MIT-OCW and things are easy now because I took it recently from my BSEE program.

A curious question is on multivariable calculus. Engineering programs here in my country PH does not have a separate multivariable calculus course but then I realized that in the differential calculus course that I have taken recently, we touched on the topic of partial differentiation and it turns out this is multivariable calculus already.