Adding proficiency to damage

Is there a way I can add proficiency to my damage on a weapon I have. I'm using the standard dnd character sheet, I'm playing a hexblade warlock and wanted to make a separate entry for when I do damage with hexblade's curse. It adds a number equal to my proficiency bonus, and I can just manually put that in there but wanted to see if I can get the sheet to do it for me. I have looked around and found some scattered info on how I might do this, but I've tried using the variable pb but it hasn't worked quite yet. I've tried putting @(pb) in there, but I don't really know what the correct syntax is or if it even works there.

When calling an attribute the format is @{keyword|attribute} where keyword is the character name, character id, or a special keyword like selected or target. However when calling an attribute within the character sheet, you can omit this keyword.

Try this: @{pb}

ok after fiddling around with it for a bit more (of course the moment I give up and go to the forums i seem to always figure it out) I think I finally fixed it. I guess you have to add it in the box with the dice roll, doesn't seem to work if I put it in the last dialogue box after the ability modifier.

Yes, that is correct. The last box is unfortunately a flat modifier (number only, not attributes or other calculations).

there's a way to look it up. R. Click the target Stat on the Sheet, look for something like

name="attr_strength_mod" value="(floor((@{strength}-10)/2))" 

I grabbed that from the 5e Community Sheet, but if you Inspect Element on the Stat you are wanting, there's going to be SOMEthing like that there, look for attr_

Result: @{strength_mod}