Answer 1

There are two major concepts in confusion: binding and loading. It is conflated by the concept of DataBinding, which is somewhere in the middle often doing both. After considering it, I am going to add one more concept, to complete the trifecta, dispatch.
Types

Late Binding: type is unknown until the variable is exercised during run-time; usually through assignment but there are other means to coerce a type; dynamically typed languages call this an underlying feature, but many statically typed languages have some method of achieving late binding

Implemented often using [special] dynamic types, introspection/reflection, flags and compiler options, or through virtual methods by borrowing and extending dynamic dispatch
for more about how to use it:
https://www.codesdope.com/cpp-virtual-and-abstract/