Collapse data to single

1. Your data is not in a usable format. Unpivot it to make it usable.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("pZKxCsIwEIZfpWTucJdc7pLVUXBxLR1ESxWEotb3t+QUpRQa4hD+ZPh+jvvSNGY7dKY2m+vQ94/pgtaRZwnTtXqffXd7Xu7daflZmbZeayEX2f00VpnslMGndBaKeKGofKAy3qckLpxfxCovMmN3h/F4zuzw2hEKdyCckhAXeJ1jrSOgziBlHhg8/OORISSPFGORR0an/wDow3/3n9thIbn0CHOXmbyg8snHAt++AA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"First Name" = _t, #"Last Name" = _t, #"Employee Number" = _t, #"Expiry Date" = _t, #"Date  Awarded" = _t, #"Training 1" = _t, #"Training 2 " = _t, #"Training 3" = _t, #"Training 4" = _t, #"Training 5" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Expiry Date", Int64.Type}, {"Date  Awarded", Int64.Type}}),
    #"Changed Type1" = Table.TransformColumnTypes(#"Changed Type",{{"Expiry Date", type date}, {"Date  Awarded", type date}}),
    #"Unpivoted Other Columns" = Table.UnpivotOtherColumns(#"Changed Type1", {"Date  Awarded", "Expiry Date", "Employee Number", "Last Name", "First Name"}, "Attribute", "Value"),
    #"Filtered Rows" = Table.SelectRows(#"Unpivoted Other Columns", each ([Value] <> " "))
in
    #"Filtered Rows"

2.  Once you did that you can let the visual do the rest of the work.

Hi qasimawan 
Could you use Group By to achieve what you are looking for

Just copy the below code and past it into advance editor

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("pZKxCsIwEIZfpWTucJdc7pLVUXBxLR1ESxWEotb3t+QUpRQa4hD+ZPh+jvvSNGY7dKY2m+vQ94/pgtaRZwnTtXqffXd7Xu7daflZmbZeayEX2f00VpnslMGndBaKeKGofKAy3qckLpxfxCovMmN3h/F4zuzw2hEKdyCckhAXeJ1jrSOgziBlHhg8/OORISSPFGORR0an/wDow3/3n9thIbn0CHOXmbyg8snHAt++AA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"First Name" = _t, #"Last Name" = _t, #"Employee Number" = _t, #"Expiry Date" = _t, #"Date  Awarded" = _t, #"Training 1" = _t, #"Training 2 " = _t, #"Training 3" = _t, #"Training 4" = _t, #"Training 5" = _t]),
    #"Unpivoted Other Columns" = Table.UnpivotOtherColumns(Source, {"First Name", "Last Name"}, "Attribute", "Value"),
    #"Filtered Rows" = Table.SelectRows(#"Unpivoted Other Columns", each ([Value] <> " ")),
    #"Pivoted Column" = Table.Pivot(#"Filtered Rows", List.Distinct(#"Filtered Rows"[Attribute]), "Attribute", "Value", each Text.Combine(_,", "))
in
    #"Pivoted Column"