Data model conversion-Power Query

Hi Victoria-9 ,

Initial idea of how to work with multi-row headers is from Gil Raviv, at least I picked-up it here. Now don't remember there are the details, in his book or blog. In brief, transformation is like

generated script is

let
    Source = Excel.CurrentWorkbook(){[Name="Table2"]}[Content],
    MergeFirstThreeColumns = Table.CombineColumns(Source,
        {"Column1", "Column2", "Column3"},
        Combiner.CombineTextByDelimiter("=", QuoteStyle.None),"Merged"),
    TransposeTable = Table.Transpose(MergeFirstThreeColumns),
    FirstRowAsHeader = Table.PromoteHeaders(TransposeTable, [PromoteAllScalars=true]),
    UnpivoteOtherThanFirstTwoColumns = Table.UnpivotOtherColumns(FirstRowAsHeader,
        {"==", "Number=Name=Group"}, "Attribute", "Value"),
    PivotMonths = Table.Pivot(UnpivoteOtherThanFirstTwoColumns,
        List.Distinct(UnpivoteOtherThanFirstTwoColumns[#"Number=Name=Group"]),
        "Number=Name=Group", "Value"),
    SplitFirstColumnsBack = Table.SplitColumn(PivotMonths, "Attribute",
        Splitter.SplitTextByDelimiter("=", QuoteStyle.Csv), {"Attribute.1", "Attribute.2", "Attribute.3"}),
    RenameAsBefore = Table.RenameColumns(SplitFirstColumnsBack,
        {{"==", "  "}, {"Attribute.1", "Number"}, {"Attribute.2", "Name"}, {"Attribute.3", "Group"}}),
    ProperColumnsOrder = Table.ReorderColumns(RenameAsBefore,{"Number", "Name", "Group", "J", "K", "  "})
in
    ProperColumnsOrder

and file is attached.

Hope above are self-explained if repeat step by step. Didn't play with final sorting, recognised too late it's better to do one.