Hi @Dennis_Qiang ,
Could you tell me the fields' data type in your sharepoint list?
I assume that all of the fields that you listed are text type.
If so , you could set like this:
insert two drop downs to choose Product and choose WEEK
set drop down1's Items:
Distinct(listname,Product)
set drop down2's Items:
Distinct(listname,WEEK)
Insert a label to display the selected product(AAA)
insert gallery1 to display the second level items(Apple-Moon)
insert gallery2 inside gallery1 to display the third level items(moonlight)
set label1's Text:
dropdown1.Selected.Result
set gallery1's Items:
GroupBy(
AddColumns(
Filter(listname,Product=dropdown1.Selected.Result,
WEEK=dropdown2.Selected.Result
),
"project--subobject",
Concatenate(Project,"--",Subobject)
),
"Product",
"WEEK",
"project--subobject",
"highlights"
)
set one label's Text inside gallery1:
ThisItem.project--subobject
set gallery2's Items:
ThisItem.highlights

Best regards,