How to find data hierarchy level information

pls try 

let
    trans = (x)=>  Table.ReplaceValue(x,null,0,Replacer.ReplaceValue, Table.ColumnNames(x)),
    t = (x)=> Table.TransformColumnTypes(x,{{"Parent Task", type text}, {"Task", type text}}),
    from=t(trans(Table1)),
    dic = Record.FromList( from[Project], from[Task]),
    dict = Record.FromTable(Table.RenameColumns(Table.Group(from, "Parent Task", {"Value", (x)=>x[Task]}),{"Parent Task","Name"})),
    f=(lst)=>List.Combine(List.Transform(lst,(x)=>List.Transform(Record.FieldOrDefault(dict,List.Last(x)??"",{null}),(y)=>x&{y}))),
    df = List.Zip({List.Difference(List.Distinct(from[Parent Task]),from[Task])}),
    to = Table.FromList(f(f(f(f(df)))),(x)=>x),
   AddColumn = Table.AddColumn(to, "Project", each Record.FieldOrDefault(dic,[Column2])),
    SelectColumns = Table.SelectColumns(AddColumn,{"Project", "Column2", "Column3", "Column4"})
in
  SelectColumns