In a nutshell, everything between the #If and #End If declares API functions so that the rest of the code can use it. If the environment is 64 bit (VB7) they are declared in one fashion. If not, then they are declared for 32 bit. The code sets up variables and gets the current language format value (as a number of type Long) and stores that for later retrieval. It also gets the value for the French locale and uses that to set the language accordingly. If you look through the sub code, you'll see it makes calls to those API (Application Programming Interface) that were declared above. Which version is called was already settled in the #If block.
HTH
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.