Hi @Oskarkuus ,
As @WarrenBelz said, your description is a little confused to me as well. Could you please share more details of your scenario? It would be much better for you to attach some screenshots and describe more clearly. I tried to make some assumptions however they all seemed not exactly meet your demand.
Below is one of those assumptions:
I have a list with a number column as well as a Category Choices column:

The label to display multiply results within the Gallery, Text property
If(
ThisItem.Category.Value = "C",
Sum(
Filter(
test1,
Category.Value = "A"
),
NO1
) * Sum(
Filter(
test1,
Category.Value = "B"
),
NO1
) * ThisItem.NO1
)
A Gallery connecting to this list, the Label displays the counting result:

Hope this helps.
Best regards,
Community Support Team _ Jeffer Ni
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