In theory all math topics build upon more simple topics - to build a conceptual hierarchical framework.
At the bottom we may have the topic of numbers, then above that the topics of addition and subtraction, then above that multiplication and division, then somewhere above that linear algebra, etc. Each topic building upon the previous topics. A topic somewhere in the hierarchy cannot be understood without understanding the lower-level topics in which it conceptually depends.
Does such a hierarchy/framework exist? If not a hierarchy then possibly a directed dependency graph? The value of such a structure is that a student could follow a path up the hierarchy (or through a graph), knowing that if they understand all the dependencies for a given topic then they have the understanding to master it.