My first real stats course was a 300-level engineering stats class that kicked my ass pretty well.
The class had a calc 3 prereq I found the computation generally the easiest part. Truly grasping the topic takes patience and work but it's pretty rewarding. That said, it must be difficult to find genuinely insightful instructors who can make the material remotely interesting because good god it's necessary.
I think Americans do calc 1 which is the basic derivatives and integration you typically learn in high school, then calc 2 which is more like a college calculus course, then calc 3 is multi variable calculus.
I don't recall if multivariable was pushed in at the end of my differential and integral calculus course or at the beginning of my differential equations course. It's possible it was also somehow tucked into my linear algebra course (though, I doubt it).
In any case, we did cover multivariable as a pretty straightforward extension of single-variable calculus, without making it a separate course. Do I likely have some huge blindspot as a result of not spending a full course on multivariable calc?
(All of my formal education was in the U.S., for what that's worth. Though, it was an accelerated magnet program teaching middle school students algebra and trigonometry and covering geometry, calculus, linear algebra, and differential equations in high school.)
Did you cover Jacobian matrices and how to to calculate and classify local extremes in a multivariate function? Do you remember saddle points? If not you did miss multivariate.
The main thing you lose then is you don't know how to apply calculus on non linear coordinates like spherical coordinates and so on. It is useful for data analysis if your data is easier to work with after a non linear transformation, but if you don't work with that sort of thing then probably not very useful.
Then you did multivariate calculus in the linear algebra course. It isn't that strange to do it that way since the hard parts of multivariate has more to do with linear algebra than calculus.
The class had a calc 3 prereq I found the computation generally the easiest part. Truly grasping the topic takes patience and work but it's pretty rewarding. That said, it must be difficult to find genuinely insightful instructors who can make the material remotely interesting because good god it's necessary.