I would like to know if there are some in built functions for the scenario that is described below :
The input is the path of a parent folder. Wat the function must
VB6 has nothing that will do this in one click, but it's straightforward to get a list of all ZIP files (for example).
The FSO is not recommended for a couple of reasons: one, it adds a dependency, and two, it depends on scripting, which may be disabled per policy.
Anyway, here's a bare minimum example you can flesh out:
Dim Fils() As String
Dim Counter As Long
Dim CurrentFile As String
Redim Fils(0 To 999) As String
CurrentFile = Dir$(yourpath & "*.zip")
Do While LenB(CurrentFile)
Fils(Counter) = CurrentFile
Counter = Counter + 1
CurrentFile = Dir$()
Loop
Of course, you want to add limit checking, etc, and redim as needed, but this is the basic idea.