Grouping of columns to Create new Column

Hi Sandhya877 ,

I created a sample pbix file(see the attachement), please check if that is what you want.

1. Create a dimension table as below

2. Create a measure as below

Measure = 
VAR _category =
    SELECTEDVALUE ( 'Category'[Category] )
RETURN
    SWITCH (
        _category,
        "Bike Accessories",
            CALCULATE (
                SUM ( 'Table'[quantity] ),
                FILTER (
                    'Table',
                    'Table'[SubCategory1] = "Accessories"
                        && 'Table'[Subcategory2] IN { "Bike Racks", "Bike Stands" }
                )
            ),
        "All Accessories",
            CALCULATE (
                SUM ( 'Table'[quantity] ),
                FILTER (
                    'Table',
                    'Table'[SubCategory1] = "Accessories"
                        && 'Table'[Subcategory2]
                        IN {
                            "Bike Racks",
                            "Bike Stands",
                            "Bottels",
                            "Cleanign Supplies",
                            "Hydration Packs",
                            "Tires"
                        }
                )
            )
    )

Best Regards