Concatenate("Your Label Text " & CountRows(Filter('SharepointList', YourColumnName = "Your text condition" )))
For example:
The below script looks at a couple conditions and counts the items that fit the criteria. This script is placed in a Text Label.
Concatenate("Diplomas that will need to be mailed" & " Total: " & CountRows(Filter('2025SummerGradCeremony', StatusColor.Value = "Yellow" And DiplomaEarned.Value = "Yes" )))
What it looks like on the Power App