remove duplicates and merge data rows

Hi, adityavighne ;

According to your description, there are two methods for reference, one is in power query, and the other is to create a table with dax. as follows:
Method 1: In power query

Step1：Write a formula

= Table.Group(#"Replaced Value", {"ID"}, {{"Count",  each Table.FillDown(_,{"A","B","C","D","E","F"}), type table}})

Step2: Expand table

Step3:  Write a formula

= Table.Group(#"Expanded Count", {"ID"}, {{"Count", each Table.FillUp(_,{"A","B","C","D","E","F"}), type table}})

Step4: Expand table

Step5: Remove duplicate rows

The final output is shown below:

In addition, M language is as follows:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUcorzcnBRRUn5sI4sToQ5YkpmSWViQglyfm5BaUlqUUYej3zUjIT4dqggmWZ6Rl5qXhtBekwwpAqArukIDEPv+rMvJKi1OISHNrxmI+Vck7MS0xJpI8dsQA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [ID = _t, A = _t, B = _t, C = _t, D = _t, E = _t, F = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"A", type text}}),
    #"Replaced Value" = Table.ReplaceValue(#"Changed Type","null",null,Replacer.ReplaceValue,{"A","B","C","D","E","F"}),
    #"Grouped Rows" = Table.Group(#"Replaced Value", {"ID"}, {{"Count",  each Table.FillDown(_,{"A","B","C","D","E","F"}), type table}}),
    #"Expanded Count" = Table.ExpandTableColumn(#"Grouped Rows", "Count", {"A", "B", "C", "D", "E", "F"}, {"A", "B", "C", "D", "E", "F"}),
    #"Grouped Rows1" = Table.Group(#"Expanded Count", {"ID"}, {{"Count", each Table.FillUp(_,{"A","B","C","D","E","F"}), type table}}),
    #"Expanded Count1" = Table.ExpandTableColumn(#"Grouped Rows1", "Count", {"A", "B", "C", "D", "E", "F"}, {"A", "B", "C", "D", "E", "F"}),
    #"Removed Duplicates" = Table.Distinct(#"Expanded Count1", {"ID"})
in
#"Removed Duplicates"

Method 2:  Create a table with dax
You could create a new table by following:

Table 2 = 
ADDCOLUMNS( 
VALUES('Table'[ID]) ,
"A",CALCULATE(MIN('Table'[A]),FILTER('Table','Table'[ID]=EARLIER([ID]) && [A]<>"null")) ,
"B",CALCULATE(MIN('Table'[B]),FILTER('Table','Table'[ID]=EARLIER([ID]) && [B]<>"null")) ,
"C",CALCULATE(MIN('Table'[C]),FILTER('Table','Table'[ID]=EARLIER([ID]) && [C]<>"null")) ,
"D",CALCULATE(MIN('Table'[D]),FILTER('Table','Table'[ID]=EARLIER([ID]) && [D]<>"null")) ,
"E",CALCULATE(MIN('Table'[E]),FILTER('Table','Table'[ID]=EARLIER([ID]) && [E]<>"null")) ,
"F",CALCULATE(MIN('Table'[F]),FILTER('Table','Table'[ID]=EARLIER([ID]) && [F]<>"null")) 
)

The final output is shown below:

Best Regards,
Community Support Team_ Yalan Wu
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